The impact of tubing sizes

[Cathar]

I've been working on a wholistic guide to designing a water-cooling system of late. Using a mix of real-world test data, and calculating pressure drops, I've been able to put together an analysis of the impact of tubing sizes on CPU temperatures.

The radiator and waterblocks are:

Thermochill PA120.2 with 2 x Yate-Loon fans at 12v
Swiftech Apogee GTX
Conroe C2D CPU, overclocked and under load, emitting 100W of heat
2 meters of tubing length

Loop order is pump->radiator->waterblock->pump

Using 1/2" ID tubing and 1/2" OD barbs, I determined the pressure-drop curve for the system. Using Swiftech's published test data for the Apogee GTX, and a flow-performance curve for the PA120.2, we're able to determine the pumping hydraulic power required to push various flow-rates. Using established typical ratios of hydraulic power to actual power draw and heat dump of known real-world pumps, we're able to throw into the mix the amount of pump heat dump required to push any flow rate. We first establish this independently of an actual pump (i.e. determine the theoretical best pump), and then select an actual real-world pump that best suits the theoretical target, and then using the PQ curve of that pump, determine the final flow rate of the system, and hence the correspondent final CPU temperature.

Now in a wholistic model, we're modelling not just the impact of the water-flow rate on the CPU temperature, but the impact of the total heat dump of the cooling system (CPU, pump, radiator fans) has on the room environment, which in turn raises the temperature of the air in the room, and so in turn raises the water temperature because the air-in temperature into the radiator will have warmed up. The effect is very small, but I still model it.

Global temp = 22C
Room C/W = 0.005
Fan Heat Dump = 2.0W

The proposed tubing sizes and fittings we'll be investigating are:

6.35 (1/4") ID tubing with quick-fit fittings
8mm (5/16") ID tubing over 6mmID|8mmOD barbs
8mm (5/16") ID tubing with quick-fit fittings
9.6mm (3/8") ID tubing over 7.5mmID|3/8"OD barbs
9.6mm (3/8") ID tubing with quick-fit fittings
11.1mm (7/16") ID tubing stretched over 10.5mmID|1/2"OD barbs
12.7mm (1/2") ID tubing over 10.5mmID|1/2"OD barbs

Quick-fit fittings are those similar to those found on the Swiftech MCW50 (http://www.swiftech.com/products/mcw50.asp)

Running the above range of tubing/fitting sizes through the optimal pump power estimator software I wrote, it predicts that the best pump to use is one that's consuming around 10-13W, with optimal pumping efficiency in the ranges of 3-6LPM. I won't go into the intricacies of the pump power estimator. It's not an exact science, suffice to say that it looks at the wholistic scenario given a waterblock, heatload, room C/W, radiator, system restriction, and so on, and puts out a suggestion for where the optimal range of pumping power lies for that setup. This allows us to then pick a real pump that closely matches the suggested pumping characteristics.

Using the Laing data here: http://www.laing.de/file/66 we see that an unmodified DDC1+ (more commonly referred to in forums as the DDC2) is a very good pump fit for our scenario. Another excellent alternative would be the DDC1 with a modded top.

Okay, so our optimised system consists of:
Laing DDC1+ (unmodified)
Thermochill PA120.2 with 2 x Yate-Loon fans at 12v
Conroe C2D CPU, overclocked and under load, emitting 100W of heat
2 meters of tubing length

For the various tubing/fitting sizes, the PQ curves for a full system for each tubing type looks like this:

http://www.employees.org/~slf/curves/pumps/tubings.png

I overlaid the curves onto the PQ graph for the Laing DDC1+

The flow performance curves for the radiator and waterblock are illustrated on the following graphs:

http://www.employees.org/~slf/curves/pumps/tubing-block-cw.png
...and...
http://www.employees.org/~slf/curves/pumps/tubing-rad-cw.png

The total CPU heat load is 100W. The total system heat load is 114W . We assume a fixed 14W heat dump from pump which was derived from other testing. This does in fact vary a little as we can see by the Laing graph. As flow rates decrease, so does power draw, and therefore the heat-dump as well. For simplicity we'll assume a fixed 14W heat dump for now.

The intersections all are:

6.35mm quick fit = 4.45LPM flow, 0.0795 block c/w, 0.0374 rad c/w
8mm barbed = 4.75LPM, 0.0783 block c/w, 0.0373 rad c/w
8mm quick fit = 5.6LPM, 0.0770 block c/w, 0.0369 rad c/w
9.6mm barbed = 5.7LPM, 0.0768 block c/w, 0.0369 rad c/w
9.6mm quick fit = 6.2LPM, 0.0762 block c/w, 0.0367 rad c/w
11.1mm barbed = 6.3LPM, 0.0761 block c/w, 0.0367 rad c/w
12.7mm barbed = 6.35LPM, 0.0760 block c/w, 0.0366 rad c/w

Final CPU temperature is ambient (22C) + system load (114W) * radiator C/W + CPU Load (100W) * block C/W

The final CPU temperatures work out to be:

6.35mm quick fit = 34.21C
8mm barbed = 34.08C
8mm quick fit = 33.91C
9.6mm barbed = 33.89C
9.6mm quick fit = 33.80C
11.1mm barbed = 33.79C
12.7mm barbed = 33.77C

So there we have it. The differences between varying tubing sizes.

Okay, the more astute of you will point out that the block C/W is really the case-to-block C/W, and that the actual CPU-die-to-block C/W is a lot higher. Even if we triple block the C/W (which would be an absolute upper limit based upon older research), we get:

6.35mm quick fit = 50.11C
8mm barbed = 49.74C
8mm quick fit = 49.31
9.6mm barbed = 49.25C
9.6mm quick fit = 49.04C
11.1mm barbed = 49.01C
12.7mm barbed = 49.00C

I'll leave it to everyone's own personal value based judgement to determine the relative importance of the differences seen....

It's certainly not the 5C figure that people bandy about. I never expected that it ever would be myself. In my own testing with arbitrarily choking the flow-rate in a test-system, I've always been amazed at the low flow resilience of many setups. Below 2LPM is where things start getting pear shaped quickly for most systems. My recommendation is that even if you're a low-flow fanatic, always ensure that your flow-rates are above 2LPM at the very least, and preferably above 3LPM if at all possible. Still, even when given 1/4" tubing installed with quick-fits and a decent pump like a DDC2, we can see that flow-rates in excess of 4LPM aren't a problem.

[Polizei]

Excellent work. Easy to understand to boot. :up:

EDIT: Sticky +1

[Grinch]

wow:shocked: :eek:

you never cease to amaze me...:clap:

great article...:up:

voting for sticky now!:clap:

[SiGfever]

:clap: :clap: :clap: :up:
Great work.

You can tell that you are feeling better by the amount of interaction of late. :toast: :toast:

[Webster]

:clap: :clap: :clap: :clap:
Sticky please!

[nikhsub1]

:clap: :clap: :clap: :up:
Great work.

You can tell that you are feeling better by the amount of interaction of late. :toast: :toast:
Or how bored he is ROFL. A few nights ago my phone rang, it was Stew! We had a chat and I conveyed to him (great minds seem to think alike eh? :D ) that I was considering moving to smaller tubing with push fittings as I'm bored, I think it is neater and will not impact performance much at all. Now to find the proper tubing, g 1/4 and g 3/8 push style fittings - hmmmm.

[jabski]

very good :up:

+14 sticky

[jtok202]

Deserves to be stickied along with all the other guides. :) :yepp:

[MetalZone]

Thank you! Very informative. :up:

Cathar, with pumps that have less head pressure than the DDC1+/DDC2 like the D5 or perhaps something even weaker, how much of an impact would tubing size bring upon flow rates and temperatures?

[sick_g4m3r]

WOW! this is truly excellent!! stupid dies....

+3 sticky, no doubt


and can someone please enlighten me on 1/4" "push fittings"?
EDIT: sorry i reread it cause it was so good and saw the push fittings. excellent work again and again


with pumps that have less head pressure than the DDC1+/DDC2 like the D5 or perhaps something even weaker, how much of an impact would tubing size bring upon flow rates and temperatures?

yes i have this question too.



and also, i still dont get what push fittings are after looking at the link. i am confused, why are they so easy to maintain and stuff? what am i missing??

[Cathar]

Cathar, with pumps that have less head pressure than the DDC1+/DDC2 like the D5 or perhaps something even weaker, how much of an impact would tubing size bring upon flow rates and temperatures?

The more restrictive the setup, the more that the setup benefits from a more powerful pump to keep flow-rates up. We're still talking about being slightly more powerful, not massively so. Let's run some figures with a DDC1. It's weaker than the DDC2, so I predict that it'll fall behind the DDC2 a bit for the more restrictive tubing sizes, but close the gap as the tubing opens up. Let's see how it goes eh?

Well, here's the graph of the curves against an unmodified DDC1, which is the other pump I suggested would closely match the simulator's pump prediction. A fair deal weaker pump than the DDC2. Pressure head is in the ballpark of the D5. I don't have the PQ graph for the DDC1 with a modified top, so I'll run with the stock DDC PQ graph. It'll be interesting.

http://www.employees.org/~slf/curves/pumps/tubings-ddc1.png

Pump heat dump is 8.5W (measured by me in the past).

The intersections all are:

6.35mm quick fit = 3.9LPM flow, 0.0812 block c/w, 0.0378 rad c/w
8mm barbed = 4.2LPM, 0.0805 block c/w, 0.0376 rad c/w
8mm quick fit = 4.95LPM, 0.0782 block c/w, 0.0372 rad c/w
9.6mm barbed = 5.0LPM, 0.0781 block c/w, 0.0372 rad c/w
9.6mm quick fit = 5.4LPM, 0.0774 block c/w, 0.0370 rad c/w
11.1mm barbed = 5.55LPM, 0.0771 block c/w, 0.0369 rad c/w
12.7mm barbed = 5.6LPM, 0.0770 block c/w, 0.0369 rad c/w

Final CPU temperature is ambient (22C) + system load (108.5W) * radiator C/W + CPU Load (100W) * block C/W

6.35mm quick fit = 34.22C
8mm barbed = 34.13C
8mm quick fit = 33.86C
9.6mm barbed = 33.85C
9.6mm quick fit = 33.75C
11.1mm barbed = 33.71C
12.7mm barbed = 33.70C

...or tripling the block C/W

6.35mm quick fit = 50.46C
8mm barbed = 50.23C
8mm quick fit = 49.50C
9.6mm barbed = 49.47C
9.6mm quick fit = 49.23C
11.1mm barbed = 49.13C
12.7mm barbed = 49.10C

As you can see, the results are very close to the DDC2. With a modified top, I reckon that the DDC1 would be about equal to the DDC2.

The Laing D5 has about the same pressure as the DDC1, but dumps a fair amount more heat into the loop since the D5 is a more highly flowing pump, but that high flowing nature is wasted with a moderately restrictive setup with a Apogee GTX, and so it'll just dump more heat. Without calculating, a top-of-my-head guess is that you'd see results similar to the DDC1, but add on about +0.25C across the board due to the extra pump heat.

[sick_g4m3r]

wait. was the GTX and PA120.2 pressure drop factored in?

[Cathar]

wait. was the GTX and PA120.2 pressure drop factored in?

Yes, of course...

[sick_g4m3r]

really? because you said you pulled those DDC curves from the sight, meaning you didnt alter them according to the pressure drop, or what am i missing?

[Okda]

I alwasy wanted such a review to convince me that my next w/cing build will include 3/8" tubes which imho looks much better and takes less space in the case

Thanks for sharing

Sticky please

[sick_g4m3r]

wait i am still not convinced... those DDC curves are stock arent they?

[qwerty69]

Great work :clap: :clap: :clap:

3/8 with quick fit isn't bad after. :)

[Cathar]

really? because you said you pulled those DDC curves from the sight, meaning you didnt alter them according to the pressure drop, or what am i missing?

I'm not sure I'm following what you're trying to say.

The PQ curve for the pump is replicated from the Laing site. There may be some very small variations in the translation from their graph to mine. Laing have more straight-lined some sections, while I applied a measure of smoothing to the curve which is what we would really see if we plotted the PQ curve to 0.1LPM increments.

The separate curves for the system include the pressure drop of the radiator, the waterblock, the tubing, and the fittings. Where the curves intersect with the pump curve is the flow-rate that we will see.

The nature of the curves are such that if there's any errors in transcription that it affects all points equally, so while the results may alter by a few 0.01C points either way (inherent margins of error) the relative differences between each data point should be fairly fixed.

[Cathar]

i still dont get what push fittings are after looking at the link. i am confused, why are they so easy to maintain and stuff? what am i missing??

You push the tubing into a hole. There is a collet lock that surrounds and grips the tubing so you can't pull the tubing out unless you release the collet lock, and an O-ring that squishes between the inside of the hole and the outside of the tubing, creating a seal.

What makes push-fit fittings so good is that there's nothing blocking the entrance/exit of the tubing. It's not like tubing squished over a barb where the liquid has to squish through the smaller barb orifice. With push-fit/quick-fit fittings there's nothing obstructing the flow at all.

[Fairydust]

Thanks very helpful.

+sticky

[mummyz]

Sticky plz

[afireinside]

Wow... Never expected that :shock:

At least we can still say small tubes are ugly!

[Cathar]

Or how bored he is ROFL.

LOL. Consider it an act of penance.

Way back in the day, when many w/c setups were 3/8", and only some were 1/2", we had the super-hot AMD T'bird CPU's, and poorly designed open-flow waterblocks with little internal furniture that demanded that as much flow be rammed through them as possible to perform. Further, most pumps that were available were like the Eheim 1250. High-flow, low-pressure pumps that dumped a fair amount of heat, and radiators taken from cars that also demanded flow rates in excess of 10lpm to get past their performance knee.

i.e. 1/2" ID made sense then. The benefit still wasn't huge over 3/8", but it was noticeable. Tests back then showed that the move from 3/8" to 1/2" meant anything from a 0.2-1.0C improvement, depending on various factors. A 1.0C improvement was enough for most people to make the jump, and so 1/2" tubing got its following. I also feel responsible in part for the jump to the 1/2" band-wagon, since I conducted a fair few tests back then to justify it.

Fast-forwards to today, and we have well designed middling restriction blocks which are more flow agnostic. We have well designed radiators that are more flow-agnostic (both in terms of fan power and liquid flow-rate). We have pumps that are near optimal for PC water-cooling that strike a good balance between pressure, peak-flow, noise, and heat. In short, everything has, quite rightfully, been pegged back from old-school high-flow excess, and tempered with a more balanced approach.

The one thing remaining is tubing size. It's also the thing that seems to cause massive grief. Years back when running tests with the Cascade/Storm designs, I realised that flow rates didn't have to be that high. When I started factoring in pump heat coupled with radiator performance, we learned that there is such a thing as "too much pump". There really is a happy middle ground.

I saw that people loved their low-restriction 1/2" tubing, but people also complained about how big it was. I agreed. 3/4" OD tubing is rather large. People didn't want to give up the idea of the benefits of 1/2" ID tubing, so that's when I investigated and came up with the idea for 7/16"ID|5/8"OD tubing. I ran the tests and the maths. No net difference. The amount of people who adopted the smaller tubing showed just how many people were unhappy with huge tubing. People want small tubing, but that don't want to lose the performance benefits of larger tubing.

Came now to today, with me stuck in the house with injuries, and with all the blocks, pumps, and radiators getting pretty darn close to optimal, I thought it time to revisit the issue of tubing sizes in light of modern developments. Maybe I can atone for convincing so many people to go with 1/2" ID all those years ago, who are still using it, and don't realise that they don't still have to.

Also, I'm just sick of small-bore/big-bore bickering. I've always been a "middle-ground is best and cut-the-crap" kind of guy. Been running tests and for some time now I've even considered converting to 8mm ID tubing with quick-fittings because the differences are so small on modern hardware.

I just wanted to share what I've been seeing in private tests, and provide the theory behind it as well. After running the maths I've decided:

3/8" ID | 1/2" OD into 1/2" ID push-fittings is ideal
Caveat: Where very tight radii are needed, can use 5/16" ID tubing instead for those short sections. 5/16"ID|1/2"OD tubing has a 1" bend radius.

It's not small-bore, and it's not big-bore. It's the middle-ground and for the loss of ~0.05C, it's perfectly acceptable. As we add the extra restriction of GPU blocks it becomes even more justifiable.

Yeah, Swiftech have had 3/8" systems for ages now and had stuck by it in the face of a rampant 1/2" market. They were right to do so.

[ColonelCain]

Great guide cathar. This outta settle anyone who comes asking "What size tubing should I get?".
Sticky +(whatever up we are to). lol

[dinos22]

thanks for taking the time

i will certainly not change my 3/8" fittings to 1/2" after seeing this thread

i have a similar setup with DDC-2 and also a GPU block (MCW60) in the loop :)

3/8" tubing is easier to maneuver around that's for sure

[p8ntslinger676]

STICKY!!!!, amazing information, great read and teaches you a lot about system flow rates :D

STICKY STICKY STICKY!!!

[cirthix]

it's good to see some real numbers attached to things like this. thanks for the informative post :)

[1Day]

Great post and great timing for me - keep the information coming.

[LogAn'sRun]

I couldn't agree more 1Day.

Now I can see more and more why Cathar's name is attatched to EVERYTHING that I've learned in the last 2 month's of endless hours of research into WC. Simply awesome work. Thanks for the time you've put into it.

Sticky +1

[alpha0ne]

Thanks Cathar, even I can understand it all now :clap: :up:


All I need now is to work out how I'm going to change from 1/2" to 3/8" with my Silverprop Fusion Cyclone HL GPU block that comes with 1/2" std

[Top Nurse]

Great guide cathar. This outta settle anyone who comes asking "What size tubing should I get?".

Yes now we can simply point to this and say use whatever tube size you might want to use considering the pluses and minuses of your choice in tube size. If 1/2 degree C is important, now you can make an informed choice in the matter. :)

[NaeKuh]

lol... too bad theres no way to put a 3/8 fitting on my RD-30.

The quick drop fittigns would make looping one hell of an easy task.

I think my next quadcore will be on 3/8ID after reading this thread. 3/8 is seriously a lot easier to work with.

[Marci]

Great work as always Cathar! Guess now I'd better go revamp some kit specs :D


g 1/4 and g 3/8 push style fittings - hmmmm.

G3/8" - scrolly down - http://www.thermochill.com/acatalog/thermochill_accessories.html

[dinos22]

Thanks Cathar, even I can understand it all now :clap: :up:


All I need now is to work out how I'm going to change from 1/2" to 3/8" with my Silverprop Fusion Cyclone HL GPU block that comes with 1/2" std

1/2" to 3/8" converter

[dinos22]

Stew i posted the info at OCAU

i hope you don't mind

http://forums.overclockers.com.au/showthread.php?p=7409651&posted=1#post7409651

i rehosted the images on imageshack though

[Sideroxylon]

Thanks Cathar, your the mf'n man!!!

[Frank M]

Good work, thanks! :clap:

[IanY]

Wouldn't the thin walls of 3/8" ID and 1/2" OD -> 1/8" thickness ? cause the tubing to collapse like there's no tomorrow?

I appreciate the fervour, but this reminds me of the faithful in a Masdarah in Islamabad (yes, I have been to Pakistan, and that's probably why I'm so militant), after the Grand Imam/Mullah/Sahib/Ayatollah has spoken.

[IanY]

Reference St. Gobain:

Tygon R-3603 3/8" ID 9/16" OD has a minimum bend radius of 1-3/8"

http://tygon.com/media/documents/S0000000000000001013/tygr3603.pdf

Tygon R-3603 3/8" ID 1/2" OD has a wall thickness of 1/16" and has a minimum bend radius of 1-1/2"

Where's this magical tubing that has a 1 inch bend radius ?

{Edit} I see.. 5/6" ID 1/2" OD has a 1 inch bend radius.. so the rage now is to use 5/16" ID (close to 1/4" ID) tubing ?

[sc00p]

Where's this magical tubing that has a 1 inch bend radius ?What about quartzglass from here (http://www.finnishspecialglass.fi/index.html) for example :D IIRC it's only few thousands per kilo plus hours :p:

[Cathar]

Where's this magical tubing that has a 1 inch bend radius ?



Caveat: Where very tight radii are needed, can use 5/16" ID tubing instead for those short sections. 5/16"ID|1/2"OD tubing has a 1" bend radius.


(sigh)

If you're looking to make an arse of yourself, at least try to pull your head out far enough to allow yourself to read. Look at item AA00023. Is that, perchance, the "magical" tubing that I exactly described, and has the "magical" properties you so sarcastically suggested did not exist?

Run along now troll. Yes, that is the echoes of laughter following you. No, don't worry. You'll get over it one day.

[IanY]

(sigh)

If you're looking to make an arse of yourself, at least try to pull your head out far enough to allow yourself to read. Look at item AA00023. Is that, perchance, the "magical" tubing that I exactly described, and has the "magical" properties you so sarcastically suggested did not exist?

Hey.. so the rage now is to use ultra small diameter tubing.

Listen, I did not call you names, and there is no need for you to call me names. I am not about to engage in your little boy antics.. which are incidently against forum rules as well.

I asked a question, and you provided an answer. I have no idea how 5/16" ID tubing fits into the equation, but oh well.

If you say so, then it is gospel I suppose.

[Cathar]

Listen, I did not call you names, and there is no need for you to call me names. I am not about to engage in your little boy antics.. which are incidently against forum rules as well.


Face it. You're just cranky 'cos after 2000+ posts of getting up everyone's noses, you never once posted anything really informational. Just hot air and chest beating attitude. Someone comes along and shows you how it's done, and now you're all bitter. Once again you have cast the first stone in name-calling by offensively implying that everyone is just a pack of religious followers, yet you then try to hold your hands up and claim that you don't engage in little boy antics.

I say to you quite truly: "Grow up!"

[Fiber9]

You push the tubing into a hole. There is a collet lock that surrounds and grips the tubing so you can't pull the tubing out unless you release the collet lock, and an O-ring that squishes between the inside of the hole and the outside of the tubing, creating a seal.

What makes push-fit fittings so good is that there's nothing blocking the entrance/exit of the tubing. It's not like tubing squished over a barb where the liquid has to squish through the smaller barb orifice. With push-fit/quick-fit fittings there's nothing obstructing the flow at all.

Cathar, the push-fit or Plug&Cool aren't to my knowledge all round on the interior.
For example the Legris LF3000 (used in Europe), are hexagonal on the inside, and still cause a restriction.
The g1/4 BSPP for 10/8 tubing push-fit is 7mm at the end, and as you move to bigger tubing, say 3/8 or 1/2, the difference between tubing diameter and the push-fit is bigger, because it still is 7mm at the end.
The only way to make them equal to the tubing inner diameter is to ream (porting) them.
Being the case, the only tubing diameter that makes sense and can truly match the diameters of the tubing with the diameter of the push-fit is the 5/16 or 8mm ID.
Then as you have to use rigid tubing, you can't use the softer Tygon, due to the differences in the wall thickness.
You can still use Tygon and Push-fit with a barbed connector, but in this case if you use the barbed connector below, as Swiftech you still have a restriction, because it's just a barb with all the inconveniences it has.
http://www.legris.com/legris_com/images/produitBM/P3122.jpg
Finally if you use the tube inserts, there's also a restriction.

Edit: You might have a look upon the Jonh Guest parts , altough I don't know if they have the same characteristics as the Legris parts.

[Burn]

Absolutely superb information Cathar- Your methodology is second to none. I think that everyone needs to have a look at this information.

The difference between 7/16 and 1/2 was interesting, considering it was so small. Then again, there is a 1/16" difference between ID's. I think that the differences might be a bit more noticeable if you were to add, say, a MCW30 chipset block and any GPU block, be it full-cover or otherwise. What say you?

[IanY]

Face it. You're just cranky 'cos after 2000+ posts of getting up everyone's noses, you never once posted anything really informational. Just hot air and chest beating attitude. Someone comes along and shows you how it's done, and now you're all bitter. Once again you have cast the first stone in name-calling by offensively implying that everyone is just a pack of religious followers, yet you then try to hold your hands up and claim that you don't engage in little boy antics.

I say to you quite truly: "Grow up!"


Hallelujah! Thank God I don't derive my self esteem from knowledge about water cooling on some internet forum ! Me cranky about not posting information? You are right. I have no information to share, because I have no such knowledge. Thank God.

You seem to take much joy in throwing stones.. I hope you don't live in a glass house.

[Pete]

Nice one Stew.

So just pure simpely in your own words which size is the best to have these days?

Hope your doing okay still after your crash too

Pete

[HiJon89]

IanY there are just some things you learn after you spend 5 minutes on this forum. For example, you don't disagree with Hipro5, OPB, Bigtoe, or Eva2000 when it comes to RAM. You don't disagree with Chilly1, PC Ice, or jinu when it comes to phase change. You don't disagree with k|ngp|n, Kinc, Sampsa, Lardarse, or OPPAINTER when it comes to 3D benching. And you sure as hell don't disagree with Cathar when it comes to water cooling. (or Maxxx or Marci for that matter)

[migueld]

What? Cathar was partially responsible for the 1/2" madness? You Darth Vader!!!!!!!!!
;)

[AndyM]

Nice to see a technical review of the tubing/flow issue. I kind of figured what you documented was happening turning my D5 to 1 and seeing no temp change. Great work! Good to dispell the escalating group-think on flow requirements.

[JargonGR]

hmmmmmmm......

[IanY]

IanY there are just some things you learn after you spend 5 minutes on this forum. For example, you don't disagree with Hipro5, OPB, Bigtoe, or Eva2000 when it comes to RAM. You don't disagree with Chilly1, PC Ice, or jinu when it comes to phase change. You don't disagree with k|ngp|n, Kinc, Sampsa, Lardarse, or OPPAINTER when it comes to 3D benching. And you sure as hell don't disagree with Cathar when it comes to water cooling. (or Maxxx or Marci for that matter)

Sir,

With all due respect, I will disagree and argue with whoever and whomever I see fit, including the Queen of England and the Emperor of Japan.

As far as I am concerned, everyone puts on their pants a leg at a time, and the last time I checked, we all sat on the potty at 3 or 4 years old, whether or not the potty was made of plastic or gold. The resulting output remains the same, no matter which continent we are on.

I will not subscribe to stuff spouted out as widely as my leaky garden hose connection to the faucet. This is the same guy, not too long ago, that swayed public opinion from 3/8 to 1/2 and then back down to 7/16, and now its back to 3/8 and he's even suggesting 5/16.
As far as I am concerned, he's just another product innovator, of which there are a baker's dozen. He's made his mark via a product, where the product's intellectual property was sold/transferred. He couldn't even yield commercial success out of the product. Reminds me of Xerox, which invented just about everything that one can mention, but could not generate any commercial success out of any of its inventions. Visions of the phrase "washed up" come to mind.

[HiJon89]

With all due respect, I will disagree and argue with whoever and whomever I see fit
Then get used to being the laughing stock of the forum :rolleyes:

[IanY]

Then get used to being the laughing stock of the forum :rolleyes:

Like I said, all are free to laugh all the time :)

[[XC] riptide]

Face it. You're just cranky 'cos after 2000+ posts of getting up everyone's noses, you never once posted anything really informational. Just hot air and chest beating attitude. Someone comes along and shows you how it's done, and now you're all bitter. Once again you have cast the first stone in name-calling by offensively implying that everyone is just a pack of religious followers, yet you then try to hold your hands up and claim that you don't engage in little boy antics.

I say to you quite truly: "Grow up!"
Ouch!

[migueld]

Ian I thought you wanted to stay off trouble? Nice bomb drop :rolleyes:

I agree with you that even the watercooling "gods" can be questioned, and in fact I think it should happen more often. But you got no real argument other than a tubing misunderstanding!

[kamongear]

IanY there are just some things you learn after you spend 5 minutes on this forum. For example, you don't disagree with Hipro5, OPB, Bigtoe, or Eva2000 when it comes to RAM. You don't disagree with Chilly1, PC Ice, or jinu when it comes to phase change. You don't disagree with k|ngp|n, Kinc, Sampsa, Lardarse, or OPPAINTER when it comes to 3D benching. And you sure as hell don't disagree with Cathar when it comes to water cooling. (or Maxxx or Marci for that matter)

If everyone agreed with you then there would be no innovation and nothing to build upon.

If I have evidence that something anyone said is wrong I sure as hell will argue about it with them no matter who they are.

Im not saying I agree with Iany on this one but I think this statement is completely false and should not be followed by anyone.

[IanY]

Ian I thought you wanted to stay off trouble? Nice bomb drop :rolleyes:

I make exceptions when I smell the foul stench in the air.

[IanY]

riptide;2248035']Ouch!

A guy that posts an infantile image from a website called plasticnipple.com wants to talk to me about growing up?

I was around before you were an itch in your ... never mind...

[HiJon89]

If I have evidence that something anyone said is wrong I sure as hell will argue about it with them no matter who they are.
What evidence could you have that such people wouldn't already know about? Any testing data you look at, they compiled. Any phase change guide you follow, they wrote. Any idea you think of, they thought of it first. By all means, feel free to argue with whoever you want, but let IanY's experiences with Cathar be a lesson to you. Mess with a legend, and you get put in your place ;)

[[XC] riptide]

A guy that posts an infantile image from a website called plasticnipple.com wants to talk to me about growing up?

I was around before you were an itch in your ... never mind...

IanY. I never told you to grow up in this thread anyway. Maybe you should reread... it was Cathar.

[nikhsub1]

I can see Ian's point to a degree (playing devil's advocate here) as he has not been around that long and is enamored with Swiftech. He has every right to say whoa! WTF? However, Stew has presented pretty credible DATA to back up what he is saying, there is no blind faith here Ian - there is data to prove what he says. Arguing against something which is proven as fact is what is know as being an idiot. There is no theory to argue against here.

Ian you love to claim that you go 'against' the masses yet, the masses here are for big bore tubing. The impact of small tubing is far less detrimental than one would expect, sure there are small differences but not enough to lose sleep over.

Where is the 'stench' you speak of? I hope you like the role of class clown because you have more than earned it.

[IanY]

I can see Ian's point to a degree (playing devil's advocate here) as he has not been around that long and is enamored with Swiftech. He has every right to say whoa! WTF? However, Stew has presented pretty credible DATA to back up what he is saying, there is no blind faith here Ian - there is data to prove what he says. Arguing against something which is proven as fact is what is know as being an idiot. There is no theory to argue against here.

Ian you love to claim that you go 'against' the masses yet, the masses here are for big bore tubing. The impact of small tubing is far less detrimental than one would expect, sure there are small differences but not enough to lose sleep over.

Where is the 'stench' you speak of? I hope you like the role of class clown because you have more than earned it.

I love the role of class clown. Enjoying every minute of it.

Are the masses here for big bore tubing? Are they? What is that 7/16" ID nonsense that been spouted on here for eons ? I use 1/2" ID religiously and I am proud of it.

I haven't been around as long? Around in XS. Yeah.

That "scientific data" in the form of more charts were also around in ProCooling when he advocated going from 3/8 to 1/2. Then from 1/2 to 7/16. Now from 7/16 to 3/8.

I guess the laws of physics change every year.

And to address your point, I question Gabe as well. You saw me give him a bit of a hard time about the Stealth. However, at least Gabe had the gumption to call a spade a spade, and when the time for the Storm was up, Gabe also told it, but you guys chose to make fun of the Apogee design instead of looking into it.

It took a 13 year old boy to scream "WTF.. Stop putting vinegar into your radiators." Even then, he got ridiculed, and nobody ever gave him any credit.

I guess low flow and low pressure is now "in"... so you guys can stop buying the Petra tops!

[[XC] riptide]

Damn... I'm getting very close to inserting into the sig.

[Marci]

Edit: You might have a look upon the Jonh Guest parts , altough I don't know if they have the same characteristics as the Legris parts.

John Guest Pushfits... there are a few versions, but of the ones we have here... (no 12mm in stock at the mo as far as I can tell/find)

G1/4" > 8mm OD tubing PM010802E = 6.5mm bore thru the fitting
G3/8" > 8mm OD tubing PM010813E = 6.5mm bore (2 diff versions of this fitting)
G3/8" > 8mm OD tubing PM010803E = 7mm bore (2 diff versions of this fitting)
G3/8" > 10mm OD tubing PM011013E = 10mm bore (but with a narrowing to 7mm at the base of the collar then back up to 10mm thru the threads)


or Marci for that matter)
Meh - argue with me on anything u like, as long as you have some evidence to support your side of the argument. If someone says "Father Christmas exists" I say "prove it". It's down to the person making the claims to provide their unbias proof (pref via double-blind testing) to back it up. No proof = worthless claim.

[GameGuru]

Ok boys and girls, back on topic here. So if were going to make a recommendation to a NOOB what would be the verdict? Lets say were using the DDC-2, a D-Tek Fuzion and a MCW60. What tubing, tubing size, barbs, pushfits etc. are we using here?

Just thought I'd try to nail it down to help some peps out.

[Terryb47]

Well based on the results of Cathars tests, it barely makes difference. choose whatever tube size you want. You won't see a few degrees between smaller sized tubing. And I can back it up.

Since I'm in Europe - I've been using 10/8 tubes for years, when I 'upgraded' to 1/2" it barely made any difference in temperature. within a degree C probably.

[Mekrel]

I love the role of class clown. Enjoying every minute of it.

Are the masses here for big bore tubing? Are they? What is that 7/16" ID nonsense that been spouted on here for eons ? I use 1/2" ID religiously and I am proud of it.


and the difference between the two is 1.6mm, they are both big bore tubing.

[beaneh]

To my mind Cathar has posted up data to rid any myths of big being better with respects to tubing so the masses are free to choose what they want and so with sound judgement. I think this is just a trolling attempt.

[Mekrel]

Well based on the results of Cathars tests, it barely makes difference. choose whatever tube size you want. You won't see a few degrees between smaller sized tubing. And I can back it up.

Since I'm in Europe - I've been using 10/8 tubes for years, when I 'upgraded' to 1/2" it barely made any difference in temperature. within a degree C probably.

Agree whole heartedly.

To me, that graph just says - choose what ever tubing you want, as it hardly makes a difference.

Taking into consideration, people choose tubing on bend radius, clarity, value for money, non stain properties.

[virtualrain]

I think there is still value in 7/16" tubing over 1/2" barbs for the budget-minded general watercooler. You can get 7/16" cheaper than borch in Russia and the fit over the 1/2" barbs is close to perfect.

Where cost is not a concern, as Mekrel says, get the tubing that has the exact properties for your application and rest easy knowing you haven't compromised on performance.

[Burn]

I think that it comes down to individual preference- Seeing the minor difference in just a CPU loop would tell us that it makes little difference what diameter we use. So if I was trying to watercool in a Shuttle case, I would use 7/16" ID 5/8" OD with some Coolsleeves to make those super-tight bends. At the same time, if I was watercooling in a Mozart case, I might go for 1/2" because there is no need for a smaller diameter tube and I can afford to lose space in such a big case.

I still would like to see a test done with at least another block. I vote Fuzion + a GPU block. Why? Because I think the differences might become more apparent as we introduce more restriction into the blocks.

[NaeKuh]

Meh - argue with me on anything u like, as long as you have some evidence to support your side of the argument. If someone says "Father Christmas exists" I say "prove it". It's down to the person making the claims to provide their unbias proof (pref via double-blind testing) to back it up. No proof = worthless claim.


http://imagescommerce.bcentral.com/merchantfiles/5084954/Deluxe%20Santa%20Claus%20wig.jpg


Sorry marci, i just had to do it :rofl: :rofl: :up:


@ Iany, i say we do what we do best. Just do your own tests and see if it does indeed not make a big difference.

3/8 Barbs and 3/8 tubing is like buying a cup of coffee for you and me. :P

[Cathar]

LOL. I don't mind people questioning me at all. I enjoy it actually and it is productive. Been wrong plenty of times.

That's not what occurred here though. IanY comes in, slagging off the forum member base, insulting me*, and then proceeds to ask questions which were already answered and explained in the text in a transparent attempt to point score. I'll play amateur psychologist and say that it is quite clear that IanY's comments are motivated with a large dose of jealousy, because he mistakes the respect that people give for studying a subject in depth, as merely just blindly following.

I could care less if people want to question or rebuke what is presented. If that's done you had better bring something other than sarcasm, or a flat-out denial to the table, and back up your statements with proof. Anything less is just yourself asking people to believe you without proof, and that more than anything defines how some religions operate.



* - anyone who has known me for long enough knows that I actually take some measure of offense at the w/c god references - I'm actually a fairly humble person and that sits very uncomfortably with me. I consider many who use the term to actually be using it derisively. I'm just a person. I pursue knowledge aggressively, and am always happy to share and discuss it. I derive satisfaction from sharing and discussing things with people, not from being unquestionably listened to.

[Cathar]

The g1/4 BSPP for 10/8 tubing push-fit is 7mm at the end, and as you move to bigger tubing, say 3/8 or 1/2, the difference between tubing diameter and the push-fit is bigger, because it still is 7mm at the end.
The only way to make them equal to the tubing inner diameter is to ream (porting) them.
Being the case, the only tubing diameter that makes sense and can truly match the diameters of the tubing with the diameter of the push-fit is the 5/16 or 8mm ID.


What you're saying is exactly why I primarily use G3/8 fittings on my blocks, and is exactly why Thermochill do on their radiators. G1/4 fittings often do have smaller orifices in the threaded section than the tubing size is.

You're quite right in that some manufacturer's parts might requiring reaming (porting) to obtain the full flow benefit.

Yes, if you use the inserts you will add extra restriction. I've used 1/2" OD tubing fittings in the past without inserts without issues. Inserts are to quick-fit fittings much like hose-clamps are to barbs. You can get by without them safely enough so long as you're not pulling and dragging on the tubing.

[NaeKuh]

Well, your studies merited enough for me to try it out.

So thats just what i'll do. If it works great for me, then hell, i'll keep it, and recomend it. But if it doesnt work out great, then i'll just tear it apart, and rebuild it to how i like it.

Its just that simple for me. :]

[Cathar]

I will not subscribe to stuff spouted out as widely as my leaky garden hose connection to the faucet. This is the same guy, not too long ago, that swayed public opinion from 3/8 to 1/2 and then back down to 7/16, and now its back to 3/8 and he's even suggesting 5/16.
As far as I am concerned, he's just another product innovator, of which there are a baker's dozen. He's made his mark via a product, where the product's intellectual property was sold/transferred. He couldn't even yield commercial success out of the product. Reminds me of Xerox, which invented just about everything that one can mention, but could not generate any commercial success out of any of its inventions. Visions of the phrase "washed up" come to mind.

Sorry, you'll have to do better than that if you want to get a rise out of me.

There are historical reasons for the tubing sizing progressions, which I actually explained in an earlier post. Once again you're just demonstrating your ignorance for the history of the subject, rather than making any valid point.

There was no sale or transfer of intellectual property. That has never taken place.

I think from pretty much the beginning that I've always stated that I never held any aspirations to make any money out of water-cooling, and to this day I've purposely operated in just such a manner, and it is exactly why I've managed to maintain a status of commercial independence on forums. I don't compete with the commercial block makers. Never have, never tried to. I've never ran the water-block production as a business, and never even tried to. I've always operated as a hobbyist paying for expensive small batch runs and merely asked people to cover costs. Someone offers to make them for me, and I look at the time I'm spending on making blocks as opposed to my real job, and I think to myself: "Why not?".

Yet again you demonstrate your ignorance for history.

I'm just a hobbyist like everyone else on these forums. I give of my time and knowledge freely. I just believe that it speaks volumes for inherent bitterness in the character of various individuals who demonstrate a problem with that. Such people probably just need a good hug, but then they'd likely reject that too because they'd either be suspicious of the person giving the hug, or believe that they weren't worthy of it.

[Cathar]

I still would like to see a test done with at least another block. I vote Fuzion + a GPU block. Why? Because I think the differences might become more apparent as we introduce more restriction into the blocks.

I'll run a scenario like in the OP for you when I get some time. Have played around with it casually, and the tubing choice is about as much of a factor as for a single CPU block system.

[ira-k]

Nice testing Cathar!! I come through every now and then to see if you have left any new posts...Glad I came through today...Appreciate you taking the time to share this with us..I have to stay with my 1/2" barbs but its nice to know its not always needed...You and Bill Adams, Robotech and many others have greatly enriched our hobby with your passion for research....Thanks Again....

[Okda]

I'll run a scenario like in the OP for you when I get some time. Have played around with it casually, and the tubing choice is about as much of a factor as for a single CPU block system.

i had the same idea like Burn

thanks for the info Cathar

[Cathar]

i had the same idea like Burn

thanks for the info Cathar

Ok. Give me a suggestion for a CPU heat-load, and a GPU heat-load that you'd like to see me plug in.

Spent the last half-hour extending the software to accommodate a CPU+GPU system. Should be ready in a bit.

As for running the Fuzion, I don't have test data for it. From what I understand the Fuzion is reasonably close to the GTX, so the scale of the tubing impact should be fairly similar for both blocks. It's not like it's going to suddenly be a massive difference between the two. They are both mini-pin block designs.

One thing for the Fuzion though is that a smaller ID fitting effectively creates an impingement jet ala Scott's testing, and would actually boost performance.

[Okda]

Ok. Give me a suggestion for a CPU heat-load, and a GPU heat-load that you'd like to see me plug in.




i don't remember the exact numbers but what about an Intel Quad Core @ 1.45~1.5vcore with a single HD2900XT or 8800GTx or even SLI or CF setup

is that possible ??

personally i am interested in a loop with a Quad Core cpu overclocked and a single high end vga card cause this will be my future setup by Q4 2007

[kamongear]

What evidence could you have that such people wouldn't already know about? Any testing data you look at, they compiled. Any phase change guide you follow, they wrote. Any idea you think of, they thought of it first. By all means, feel free to argue with whoever you want, but let IanY's experiences with Cathar be a lesson to you. Mess with a legend, and you get put in your place ;)

And that is why you my friend will never become a "legend".

The world has an infinite amount of knowledge that no one can master.

[SiGfever]

Alright, my system has been getting boring and redoing my loop sounds like fun. Now which 1/2" push fittings to use? :shrug:

Thanks again Cathar this definitely needs to be stickied. :yepp: :yepp:

Hey Alex, how's the 3/8"id x 1/2"od Tygon stock?

[Cathar]

i don't remember the exact numbers but what about an Intel Quad Core @ 1.45~1.5vcore with a single HD2900XT or 8800GTx or even SLI or CF setup

is that possible ??

personally i am interested in a loop with a Quad Core cpu overclocked and a single high end vga card cause this will be my future setup by Q4 2007

Okay, did a bit of poking around. There's no hard and firm figures about, but I'll model for a 120W CPU heatload (overclocked dual-core at full-load) with a 150W GPU power (overclocked 8800GTX), which seems to be in the rough ballpark for heat dump. This seems to be more of a standard sort of system that more people would own.

An overclocked quad-core system with SLI 8800GTX overclocked, would be more like 200W CPU heatload, and 300W heat-load for the GPU's. That's just a freaky heatload in my opinion. If anyone's going to spend that sort of dosh and go to that extreme, just go buy an RD30, or 2xDDC2's in series, and use 1/2", and never mind about trying to be efficient. A quick run of the simulator says to just go all out with such a beastly machine. The radiator is going to be the major limiting factor in such a setup, what with ~550W of heat load including the pumps. Spend your money on getting as much radiator power as possible, and don't worry so much about the pump heat load. The old tried and true rules of excess is best dominates this scenario.

So yeah, I'll model for the more general case, that being a CPU+GPU setup that's affordable and doesn't generate more heat than a small nuclear explosion. ;)

[HiJon89]

And that is why you my friend will never become a "legend".
I can't wait to prove you wrong, friend.

[Grinch]

I know if cathar does some testing/benching...you can take it to the bank!

[afireinside]

This is the same guy, not too long ago, that swayed public opinion from 3/8 to 1/2 and then back down to 7/16, and now its back to 3/8 and he's even suggesting 5/16.

Did you even READ the original post? He completely explained it. Heatercores and more primitive block designs benefited much more from the higher flow 1/2" tubing and we were using pond pumps. A maze 3, heatercore, and eheim 1250 setup was a completely different the researched and designed components you're buying off the shelf for the sole purpose of computer cooling.

Plus no one has ever even done thorough 1/2 vs 3/8 and smaller tests. How can you be claiming he's a sort of hypocrite when, up to this point, there was no thorough data of any kind comparing different tubing sizes other than 1/2" and 7/16".

[serialk11r]

I can't wait to prove you wrong, friend.

HiJon, he's right...the "OMFG I MUST WORSHIP THE GODS" attitude is exactly what's causing a lot of problems.

Thank you Cathar for sharing this with us.
But I think there's a problem, there is simply no way the pump dumps ALL the heat it generates into the water, but here you've done pretty much exactly that.

[Grinch]

IanY...trust me...this is an uphill battle...you are dealing with a PIONEER of watercooling...he is not from [H]...he is [H]ardcore.

[HiJon89]

HiJon, he's right...the "OMFG I MUST WORSHIP THE GODS" attitude is exactly what's causing a lot of problems.
I trust Cathar's testing methods and when he gathers empirical data I tend to listen, it has nothing to do with worshiping Gods and everything to do with respect.

[Grinch]

I trust Cathar's testing methods and when he gathers empirical data I tend to listen, it has nothing to do with worshiping Gods and everything to do with respect.

exactly what I was thinking..:yepp:

[serialk11r]

For example, you don't disagree with Hipro5, OPB, Bigtoe, or Eva2000 when it comes to RAM. You don't disagree with Chilly1, PC Ice, or jinu when it comes to phase change. You don't disagree with k|ngp|n, Kinc, Sampsa, Lardarse, or OPPAINTER when it comes to 3D benching. And you sure as hell don't disagree with Cathar when it comes to water cooling. (or Maxxx or Marci for that matter)
Ahem...
Please don't say this kind of stuff...that's what I was referring to. If you have a valid point, and valid support for that point, then by all means disagree with them if they said something you think is wrong. The support is the big thing, if you make up random crap then SOMEONE will probably have pointed it out, and hopefully the people on the forum figure it out for themselves :P

[Cathar]

But I think there's a problem, there is simply no way the pump dumps ALL the heat it generates into the water, but here you've done pretty much exactly that.

Actually I didn't. I've measured the ratio of power draw to heat dump for a number of pumps. In general most pumps dump 85-90% of their power draw into the water directly as heat, and I actually factored that into the calculations.

I model the heat-dump of the pump into the water, and the related heat dump of the pump into the air as two separate entities.

[dinos22]

:ROTF: fantastic thread

somehow i don't think IanY is accepting anything Cathar says :D keep it up guys :clap:

i do understand what the argument is that IanY is hiding behind which is not only insulting Cathar but anyone that accepts any of his research. It's all good though we'll just do the usual blind following of Stew's factual work and enjoy the odd "ownage" comment :D. I must say it's becoming poetic almost.

i do question members if i feel they may have it wrong myself......but not like this....this is just comedy central :hehe:

[edit]Stew i should have ran it by you before i posted on OCAU about your findings lol.....ah well what's done is done >>> talk about getting owned hahhahah

[HiJon89]

Ahem...
Please don't say this kind of stuff...that's what I was referring to. If you have a valid point, and valid support for that point, then by all means disagree with them if they said something you think is wrong. The support is the big thing, if you make up random crap then SOMEONE will probably have pointed it out, and hopefully the people on the forum figure it out for themselves :P
In the case that you believe a well-known member is mistaken and you believe your evidence is sufficient to prove your point, then by all means go ahead. But proceed with caution, because 99.9% of the time it's just someone running their mouth who thinks they know everything when in fact they're completely wrong.

[Cathar]

Okay, accept this as a completely estimation. Haven't cross-checked the validity of this data, and it's what is spat out of the first stage of the estimation software process. I haven't mapped this back onto an actual pump and flow-performance curves yet, but in general the scale of the results between the first stage simulator and the final real-world validation don't differ by much at all.

I modelled a 120W CPU, and a 150W GPU. I used the Swiftech supplied data for the Apogee GTX, and the MCW50. I applied a fudge factor of 3x, as in I multiplied the Swiftech supplied C/W values by 3, purely because the supplied C/W values seem to be indicative of Tcase to block, and not Tdie to block. In multiplying the Swiftech C/W values by 3, I seem to arrive at CPU/GPU temperatures that are also more in-line with real-world seen die temperatures.

Incidentally, this scenario is where something like a RD30 would come into its own, or possibly 2 x DDC2's (unmodified). For this scenario I'll assume a level of pump power akin to a top modded DDC2.

i.e. The setup is:
C2D CPU overclocked & under load @ 120W
8800GTX GPU overclocked & under load @ 150W
Apogee GTX on CPU
MCW50 on GPU
top-modded DDC2 (21W pump)
Thermochill PA120.2 with 2 x Yate-Loon
2m of tubing

i.e. I've applied a fudge on a fudge here, and in doing so have potentially amplified the nature of the differences (as opposed to reduced them).

1/4" QF : CPU = 62.33C, GPU = 52.28C
5/16" barbs: CPU = 62.31C, GPU = 52.27C
5/16" QF: CPU = 61.48C, GPU = 51.39C
3/8" barbs: CPU = 61.56C, GPU = 51.47C
3/8" QF: CPU = 61.13, GPU = 51.01C
7/16" barbs: CPU = 61.03C, GPU = 50.91C
1/2" barbs: CPU = 61.03C, GPU = 50.91C

Using an "optimal" pump (~34W estimated) would knock around 0.1C off the temps of both CPU/GPU. In fact, after running these for a while now, it seems that the "optimal pump power" is roughly proportional to your CPU+GPU heat load divided by 8. May be a dumb rule of thumb, but it seems to be holding roughly true.

To do the full deal will require more time. I have to attend to my job now.

[Okda]

WOW
so the sweet spot is the 3/8" QF tubes
Thanks Cathar for the info

[serialk11r]

Okay I know this is a little off topic, but here it goes.
Petra calculated that the DDC-2 is about 15% efficient. The other 85% has no place to go except to be turned into heat. Common sense says that part of that heat is going into the air, the PCB, the plastic housing, and eventually...into the air from those. Another part is going into the water. Here it doesn't matter that much because its only a few watts at most. And I'm sure plenty of people have reported that their pump's cases get a little warm during operation, meaning a good deal of the heat is NOT going into the water...

[gosmeyer]

I love to see a man on a mission.
Remember, You can lead a horse water but you can't make them drink.

[dinos22]

it would be interesting what the figures are like with the 10W pump you initially used

0.1C difference doesn't seem all that much if you jump to Iwaki :confused: I am not sure what you mean there though????? Is that a proportional measure or actual difference?

[Cathar]

Okay I know this is a little off topic, but here it goes.
Petra calculated that the DDC-2 is about 15% efficient. The other 85% has no place to go except to be turned into heat. Common sense says that part of that heat is going into the air, the PCB, the plastic housing, and eventually...into the air from those. Another part is going into the water. Here it doesn't matter that much because its only a few watts at most. And I'm sure plenty of people have reported that their pump's cases get a little warm during operation, meaning a good deal of the heat is NOT going into the water...

Yeah, I use 16% efficiencies in my calculations when mapping from hydraulic power (restriction x flow) to estimated required pump power (power draw). I then multiply that value by 0.9 to arrive at the pump heat dump directly into the water. This is all in the estimation stage.

A DDC2 is 18-20W. At a 90% water heat dump, 2W is going into the bits not touched by water. Hook up a common DC electrical resistor to a DC power supply, and feed 2W of power through it. Wait 1 minute and touch it, and let me know if it doesn't dang near burn your finger off. That's the sort of heat that you're feeling from the bottom of a DDC. Blow some air over it and it'll feel cool all the time. Most pumps sit on their bottoms with no air-flow. Give anything small 2W of heat load and sit it where it gets no air-flow, and it WILL get quite warm.

Yer typical high-performance GPU ram chip generates around 2W of heat when under load. Touch one without a heatsink on it after its been working away for a while and you'll just about scorch your skin.

Remember, temperature != heat.

[serialk11r]

Yeah but what I'm saying is the housing is plastic...and all plastics are poor conductors of heat. Anyways I understand this is all in the estimation stage and stuff.
Well anyways enough off topicness :P

[Cathar]

it would be interesting what the figures are like with the 10W pump you initially used


Add ~0.3C to the CPU, ~0.5C to the GPU pretty much across the board when compared to the DDC2.



0.1C difference doesn't seem all that much if you jump to Iwaki :confused: I am not sure what you mean there though????? Is that a proportional measure or actual difference?

Your CPU and GPU will be ~0.1C cooler when using an Iwaki RD30 as opposed to a top-modded DDC2, is what I meant.

[Burn]

Great work! So even as heat load and an addition of a block, the results still vary very little (say that 10x!) I would have thought that with the addition of both more restriction and the addition of a higher heat load, the larger ID tubing would have shone though. Apparently I was mistaken!

Even if it is theoretical data + fudge, I still think that there is enough accuracy in the program that the real-world tests would come to within, say, 3-5% of the theoretical. Great work, my friend :D

[Cathar]

Yeah but what I'm saying is the housing is plastic...and all plastics are poor conductors of heat. Anyways I understand this is all in the estimation stage and stuff.
Well anyways enough off topicness :P

Plastic conducts heat poorly, and thats just the problem. The air in the pump PCB section will be getting hot 'cos the heat can't escape 'cos of the plastic surrounds. Eventually the plastic surrounds will warm up a fair bit due to the temperature of the air inside the pump. If you insulate something well enough, it doesn't matter if you give it 0.1W of heat-load, it will continue to get hotter and hotter if the heat can't escape to somewhere else.

[SiGfever]

Add ~0.3C to the CPU, ~0.5C to the GPU pretty much across the board when compared to the DDC2.



Your CPU and GPU will be ~0.1C cooler when using an Iwaki RD30 as opposed to a top-modded DDC2, is what I meant.
With such a small heat gain from the Iwaki the RD30 is looking even more appealing from a reliability standpoint.

[TheJollyFellow]

Great data Cathar! I *do have to wonder, however, why this kind of testing wasn't done by companies (I'm aware that Swiftech has kept 3/8" around, but they still haven't advertised the difference, or lack there of...), who spend a lot money developing and selling this kind of technology...makes ya' wonder ;)

Anywho, this is GREAT news for the 'small' future of computers; as more and more people start using SFF cases, tighter bend radii will be needed, and now that we *know there isn't much of a difference, it'll make the transition that much smoother :)

[dinos22]

Add ~0.3C to the CPU, ~0.5C to the GPU pretty much across the board when compared to the DDC2.



Your CPU and GPU will be ~0.1C cooler when using an Iwaki RD30 as opposed to a top-modded DDC2, is what I meant.

i guess the only reason you'd want an Iwaki is for reliability (so they say) lol

those differences are so minuscule it's mind boggling

i am learning today :)

[Grinch]

I thought about going to an rd30..but after contemplating going through the hassle of getting a meanwell converter and mounting it..etc...the ddc2 was more appealing,smaller,and a helluva lot easier to deal with..

[RickCain]

that I was considering moving to smaller tubing with push fittings as I'm bored, I think it is neater and will not impact performance much at all. Now to find the proper tubing, g 1/4 and g 3/8 push style fittings - hmmmm.

You just made me smile!

This is great data provided by Cathar and should bring a sense of calm regarding the "high flow / low flow" fights on multiple forums. :up:

[nikhsub1]

Great data Cathar! I *do have to wonder, however, why this kind of testing wasn't done by companies (I'm aware that Swiftech has kept 3/8" around, but they still haven't advertised the difference, or lack there of...), who spend a lot money developing and selling this kind of technology...makes ya' wonder ;)

Anywho, this is GREAT news for the 'small' future of computers; as more and more people start using SFF cases, tighter bend radii will be needed, and now that we *know there isn't much of a difference, it'll make the transition that much smoother :)
Tis a very slippery slope what you ask. First, people as a whole do not trust mfgr data - this is just fact. If company xxx came in here and said what Stew said, they would likely be laughed out of here and the thread closed in short order. There is one mfgr in particular (won't mention names) that presents VERY good data that is often balked at - I have been guilty of this myself. This company has been very discouraged at times of this attitude (and rightly so IMO) and has seriously considered releasing no data whatsoever (would be a mistake IMO). So you see, the mfgr's make their wares and it is up to (IMO) the unbiased users with a brain (see Cathar for example) to decipher the crap from the good.

[sick_g4m3r]

The PQ curve for the pump is replicated from the Laing site.

hold the phone. this means the PA120.2 and GTX pressure drops weren't factored in....so all the data would be different...right?

[Cathar]

hold the phone. this means the PA120.2 and GTX pressure drops weren't factored in....so all the data would be different...right?

:confused: You asked me that exact question before, and the answer I gave was that the radiator and water-block pressure drops are factored into the system PQ curves that intersect with the pump PQ curve.

[sick_g4m3r]

The separate curves for the system include the pressure drop of the radiator, the waterblock, the tubing, and the fittings. Where the curves intersect with the pump curve is the flow-rate that we will see.

yeah i asked that, and you replied you copied it exactly from the website, but it is the tubing curves that you altered, not the DDC curve. the DDC curve also must include the pressure and flow drops to obtain the correct data

[Cathar]

yeah i asked that, and you replied you copied it exactly from the website, but it is the tubing curves that you altered, not the DDC curve

Why would I want or need to alter the DDC curve?

[sick_g4m3r]

Why would I want or need to alter the DDC curve?

Because those figures will not be the same with the parts used

[Cathar]

Because those figures will not be the same with the parts used

The DDC curve operates against some level of restriction. I factored the current 3/8" fittings on the pump into the system restriction curves. When I modelled the different fitting types, I can determine the impact in one of two ways:

1) Alter the pump's PQ curve based upon the fittings on it
2) Factor the fitting impact into the system's PQ curve, and intersect that with a constant pump PQ curve.

There may be very marginal variations between the two, but as I said, the nature of the shapes of the curves is such that any variations impacts everything roughly equally.

It's just easier to do #2.

[sick_g4m3r]

ok i guess i see now. thanks for explaining yourself

[Petra]

Petra calculated that the DDC-2 is about 15% efficient.

...mmmkay... was this some random guesstimate that I happened to have mentioned over AIM or something (likely based on testing that Lee did)? Because, up until just now (since you brought it up), I hadn't run the calculations with my own data (which has already been published in XS).

After doing a little graphing and some rough calculations, I came to the following (all at peak pumping power):

Stock DDC-2: ~17% efficient (~3W max pumping power, ~18W total consumed)
Stock DDC-3.2: ~13% efficient (~2.1W max pumping power, ~16.32W total consumed)
DDC-2 w/DDCT-01s top: ~21% efficient (~4.25W max pumping power, ~20.64W total consumed)
DDC-3.2 w/DDCT-01s top: ~19% efficient (~4.2W max pumping power, ~22.32W total consumed)


hold the phone. this means the PA120.2 and GTX pressure drops weren't factored in....so all the data would be different...right?
The pressure drop incurred by the components used doesn't change the overall performance characteristics of a pump (there's a reason why you see intersecting curves in the first graph that Stew posted... The red curve represents how the pump performs (flow) at all head pressures attainable by the pump, the other curves represent the pressure drop of the cooling components used vs. flowrate, and the point of intersection represents the head pressure at which the pump operates and flowrate the pump attains given the components attached to it).

Hopefully that'll clear things up a little for you.


Anyway, interesting information, Stew... :up:

[sick_g4m3r]

The pressure drop incurred by the components used doesn't change the overall performance characteristics of a pump (there's a reason why you see intersecting curves in the first graph that Stew posted... The red curve represents how the pump performs (flow) at all head pressures attainable by the pump, the other curves represent the pressure drop of the cooling components used vs. flowrate, and the point of intersection represents the head pressure at which the pump operates and flowrate the pump attains given the components attached to it).

Hopefully that'll clear things up a little for you.


there we go! thats just what i needed, thanks a ton. and again, amazing info cathar

[Jedda]

Yeah the point at which push comes to shove, as it were.

[serialk11r]

Petra you brought that efficiency thing up about 4 months ago or so, when I made my rant thread ;)

[Petra]

Petra you brought that efficiency thing up about 4 months ago or so, when I made my rant thread ;)

A half-baked guesstimate that I actually posted? Hmm... I blame your rant :rolleyes: ;)

[Cathar]

Yeah, I use 16% efficiencies in my calculations when mapping from hydraulic power (restriction x flow) to estimated required pump power (power draw). I then multiply that value by 0.9 to arrive at the pump heat dump directly into the water. This is all in the estimation stage.


Got a correction to this. Checked the code and I'm actually using a 17% assumed efficiency in the software estimator. I forgot that I had changed it a while back.

It's fairly rare that a pump is operating exactly at its BEP (Best Efficiency Point) in any setup, and that's why I had chosen a value of 17%, which provides a guided value that more closely approximates what will happen in reality across a broader range of scenarios.

[kevinbo03]

Wow, some very interesting information!

I hope this affects manufacturing designs, I for one would prefer 1/4" tubing. So much more compact and flexible, However I wouldn't be surprised if pumps with stock 1/4" barbs operated significantly louder per GPM; Much like 80mm Vs 120mm fans.

Rated 5/5 :up:

[C'DaleRider]

Thank you, Cathar, for the empirical data on this subject. This goes a long way in settling a lot of the constant bickering on tubing and diameters needed.

Of course, I've talked with more than one member that admitted, in private typically, that when they converted from 3/8" to 1/2" or 7/16", they rarely saw the dramatic decreases in temps. that were "supposed" to happen as one would think from reading a LOT of the posts around here.

:)

[Cathar]

Part No. 51025K187 over at www.mcmaster.com appears to be pretty much what I had in mind for a 1/2" OD push-lock fitting. Will fit to 1/4", 3/8" or 1/2" NPT pipe thread size. Technical drawing appears to show that the port ID to be 3/8" ID (i.e. no flow resistance), and appear to show that you could happily apply these with an O-ring seal on the thread section for easy sealed fitment.

Part No. 51235K117 is also another example. It says rated for air only, but it's butyl/delrin, so for use with water should be fine.

Part No. 5111K87 also looks to be the goods.

[serialk11r]

Wow, some very interesting information!

I hope this affects manufacturing designs, I for one would prefer 1/4" tubing. So much more compact and flexible, However I wouldn't be surprised if pumps with stock 1/4" barbs operated significantly louder per GPM; Much like 80mm Vs 120mm fans.

Rated 5/5 :up:

...the size of the fittings is not exactly related to the RPM...They can make the barbs whatever size they want, but if the impeller and motor are the same don't expect much to happen.

[Cathar]

If anything, based upon experience with various pumps, adding more restriction causes a pump to spin more slowly (a little bit) and cuts down on noise levels.

[dinos22]

this is a bit OT but with the knowledge base in this thread might be worth asking anyways

is it a good idea to control pumps like the DDCs with a fan controller (my can controller takes around 18 or 20W per channel so i could in fact lower the RPMs?

how would that affect the pump

[sick_g4m3r]

this is a bit OT but with the knowledge base in this thread might be worth asking anyways

is it a good idea to control pumps like the DDCs with a fan controller (my can controller takes around 18 or 20W per channel so i could in fact lower the RPMs?

how would that affect the pump

no because starting amperage required exceeds that of normal running, thus requiring a peak of 25-30W at startup and frying the controller

[dinos22]

no because starting amperage required exceeds that of normal running, thus requiring a peak of 25-30W at startup and frying the controller

oh i see

damn

looks like i'll have to find a more powerful one then hahahahah

[Cathar]

Also would want to be careful that it's not a PWM based fan controller. That'll destroy the pump fairly quickly.

I have a Vantec Nexus fan controller. Yeah, one of the ones that people have a love/hate relationship with. I like mine. One day without thinking I plugged a Laing D5 into it to see how it'd go, completely forgetting about that it only has a 12W per channel power rating. It handled the load fine until I realised what I had done. I touched the PCB of the controller and it was roasting hot! Unplugged the pump quickly and the controller was fine.

You might get away with a DDC1 on a fan controller, but not a DDC1+/2.

[_G_]

a little ot but how did you manage to get yourself housebound?
get well soon but stick around the forums:toast:

[sanhacker]

Also would want to be careful that it's not a PWM based fan controller. That'll destroy the pump fairly quickly.

I have a Vantec Nexus fan controller. Yeah, one of the ones that people have a love/hate relationship with. I like mine. One day without thinking I plugged a Laing D5 into it to see how it'd go, completely forgetting about that it only has a 12W per channel power rating. It handled the load fine until I realised what I had done. I touched the PCB of the controller and it was roasting hot! Unplugged the pump quickly and the controller was fine.

You might get away with a DDC1 on a fan controller, but not a DDC1+/2.

This has me concerned. mCubed advertises the ability to run pumps via the BigNG. Is this inaccurate?

[dinos22]

Also would want to be careful that it's not a PWM based fan controller. That'll destroy the pump fairly quickly.

I have a Vantec Nexus fan controller. Yeah, one of the ones that people have a love/hate relationship with. I like mine. One day without thinking I plugged a Laing D5 into it to see how it'd go, completely forgetting about that it only has a 12W per channel power rating. It handled the load fine until I realised what I had done. I touched the PCB of the controller and it was roasting hot! Unplugged the pump quickly and the controller was fine.

You might get away with a DDC1 on a fan controller, but not a DDC1+/2.

lol i better stay away

actually mine is a Nexus but the spec says 18W per channel lol

i have DDC2 18W pump lol so that will probably kill it fairly quickly hahaha

[ranker]

This has me concerned. mCubed advertises the ability to run pumps via the BigNG. Is this inaccurate?

The BigNG can run a pump just fine. People have reported that they can run two. However, for two or more pumps, I'd recommend going with the miniNG add on.

[migueld]

Careful about pumps and controllers: when undervolting my DDC on my bigNG the bigNG's heatsink gets extremely hot, about 50-60 degrees Celcius. It seems the "saved" energy gets converted into heat :down:

[alpha0ne]

Running any electric motor with lower than spec V rating will cause it to overheat and maybe even kill it :down:

Thanks for the push/pull fittings link Cathar, I hope they ship to AU ;)

[Jedda]

Yeah but how cool is it to WC your fan controller!
An excuse for yet another loop.

[ranker]

Yeah but how cool is it to WC your fan controller!
An excuse for yet another loop.

Sorta like people who put fans on their pumps. Ironic isn't it.

[Ambro]

quote - Yeah, Swiftech have had 3/8" systems for ages now and had stuck by it in the face of a rampant 1/2" market. They were right to do so. ....:cord:

Nice, very nice.

Moral of this story - do what is proven to be right and what you think is best despite others opinions (even if they have a post count of 10,000,000)

[septim]

jedda, ranker its the classic egg or chicken which one came first...

"xs liquid cooling, every degrees C matters" hmm whatever happened to this motto... that temp diff from small to large tubing could mean more OCing potential to a user.

so its usually up to the end user which size he or she can manage...

[NaeKuh]

:ROTF: fantastic thread

somehow i don't think IanY is accepting anything Cathar says :D keep it up guys :clap:

i do understand what the argument is that IanY is hiding behind which is not only insulting Cathar but anyone that accepts any of his research. It's all good though we'll just do the usual blind following of Stew's factual work and enjoy the odd "ownage" comment :D. I must say it's becoming poetic almost.

i do question members if i feel they may have it wrong myself......but not like this....this is just comedy central :hehe:

[edit]Stew i should have ran it by you before i posted on OCAU about your findings lol.....ah well what's done is done >>> talk about getting owned hahhahah


No, i think iany just got bored.

If you read cathars exception of a small nuclear reactor, thats iany.

He has the quad with dual sli 8800GTX. And im not far from it either. :P

So i guess i am going back to 7/16

@cathar, 51025K187 <--- mcmaster-carr product, will that work on 7/16 tubing? Im kinda sick and tired of regular barbs at this moment, and wanted to try something much faster and easier. Of course my RD-30 will still use worm clamps tho.

[IanY]

No, i think iany just got bored.

If you read cathars exception of a small nuclear reactor, thats iany.

He has the quad with dual sli 8800GTX. And im not far from it either. :P

So i guess i am going back to 7/16


Oh... don't state what I have unless you receive documentary proof ! A "small nuclear reactor" is what I allegedly have, but you don't know, do you? Do you know for sure its not "all fluff and no stuff?" No, you don't know for sure :)

[ranker]

jedda, ranker its the classic egg or chicken which one came first...

"xs liquid cooling, every degrees C matters" hmm whatever happened to this motto... that temp diff from small to large tubing could mean more OCing potential to a user.

so its usually up to the end user which size he or she can manage...

Agreed. For some that 1C is something they'll chase for. For others, it's something they can live without. For the most part xtremesystems has always been about how hard you can push whatever you got. It's the same how some purchased a GTX after owning a GT where there was an estimated 1c-2c difference in temps based on prelim reports. People stilled jump at it as they wanted that 1C or 2C desperately.

Just find what it is you're looking for. If you're looking for rock bottom temps, stick with the larger tubing. If you prefer easier tubing management, go with 3/8" or "medium flow" as Cathar coined it. This post proves that 3/8" (medium flow) is a viable option for those who prefer smaller tubing without too large of a performance hit. Like someone else mentioned, funny how Swiftech had it right for so long and how Gabe and co still used it in their machines this whole time.

[IanY]

Like someone else mentioned, funny how Swiftech had it right for so long and how Gabe and co still used it in their machines this whole time.

And unlike what Scott (Nikhsub1) says, don't for a moment believe that I give only Cathar grief over what I disagree and let Gabe go free. I've been on Swiftech's case for a long time about small tubing, yes including 7/16".

[NaeKuh]

Oh... don't state what I have unless you receive documentary proof ! A "small nuclear reactor" is what I allegedly have, but you don't know, do you? Do you know for sure its not "all fluff and no stuff?" No, you don't know for sure :)

a little blue bird told me iany. :rolleyes:

heh...

also whats wrong with 7/16ID tubing. This i know for a fact gives almost no performance redutions from 1/2ID. And yeah i tested this quite a few times. Thats why i have up on tygon 1/2 unless i really need it.

[IanY]

Nothing's wrong with 7/16" :) Its perfectly good tubing. :) Doesn't mean that I have to accept it, and that's the point. I don't have to use what is popular, nor do I have to accept what is popular as the written gospel.

[IanY]

Remember my rant about the Stealth? I gave Gabe a hard time because it shows no temp improvement over the MCW60 even on the gpu core, notwithstanding the improved GTX/GT base.

I will walk through walls of fire for a 1 degree change in temperature. If it were not for my wife, I would run the room airconditioner in my personal study (a small room with a 12,000 BTU wall unit!! ) in the middle of winter where it is -5 degrees F outside, just for that extra lower load temps.

I understand many people are not willing to go to such lengths, but its up to them. I'll just continue doing what I need to do.

[NaeKuh]

Remember my rant about the Stealth? I gave Gabe a hard time because it shows no temp improvement over the MCW60 even on the gpu core, notwithstanding the improved GTX/GT base.

I will walk through walls of fire for a 1 degree change in temperature. If it were not for my wife, I would run the room airconditioner in my personal study (a small room with a 12,000 BTU wall unit!! ) in the middle of winter where it is -5 degrees F outside, just for that extra lower load temps.

I understand many people are not willing to go to such lengths, but its up to them. I'll just continue doing what I need to do.

ahahahahaha... so true.

I think your moto was, i dont care how fugly it is, as long as its king.


For me, i think looks has about 40% to do with parts. 60% on performance. If the RD-30 wasnt so blingy, i would of done 4DDC-2 2-alphacool 2in1 tops. :T

[IanY]

If the RD-30 wasnt so blingy, i would of done 4DDC-2 2-alphacool 2in1 tops. :T

You should see the latest on pumps and flow being over-rated... that you need no more than one DDC+ in your loop, and anything more would just be heating up the water... hey... I thought I held the patent for the four pumps into two Alphacools lol :D

[Cyprio]

This has me concerned. mCubed advertises the ability to run pumps via the BigNG. Is this inaccurate?

You could always use an Aquacomputer USB Poweradjust that was specifically designed to control a Laing DDC. :) You'll have to get one for each pump though.

[Cathar]

Like someone else mentioned, funny how Swiftech had it right for so long and how Gabe and co still used it in their machines this whole time.

They were right in the same way that if you wear some old bit of clothing that was once fashionable, it'll eventually come back into fashion again.

Historically there were justifiable reasons for going with 1/2" tubing. In the specific case of Swiftech though, their 5yo old MCW462 design, the inlet into the block was in itself a jet impingement effect. By using smaller tubing (3/8") the MCW462 saw a boosted jet speed onto the base-plate that overcame the flow-rate impact penalties seen with the pumps of the day. Also, Swiftech did the right thing, and used quick-fits, so these two factors combined meant that 3/8" was the better choice for their block design. The MCW5000 block followed, and that had a flow-agnostic thick base-plate, so once again the reduced flow had minimal impact. The MCW6000 followed, once again with a "the fitting is the impingement jet" design, coupled with a thick flow-agnostic base-plate, and so yet again 3/8" was justified.

The rest of the market pursued other designs where 1/2" was more justifiable, at least until fitting-independent accelerator plates and flow-agnostic internal structure was researched and more properly understood. Further, as block restriction was added to boost performance, this in turn increased the pumping power required, and soon it was discovered as people explored using more powerful pumps that pump-heat dump was playing a significant role in the final CPU temperatures. In time, the need for >6LPM flow-rates to achieve good performance, once pump heat dump is factored in, diminished. To a fair degree, it's quite possible to design a system & waterblocks to suit, where flow rates >4LPM are never required to achieve maximum performance.

At 4LPM flow-rates, even 5/16" (8mmID) tubing with quick-fits presents a minor hurdle to overcome for the pump. At 8LPM flow rates the resistance of the tubing quadruples and becomes very significant. Design every waterblock in the system to operate well at 4-5LPM, creating a level of restriction where pump heat becomes significant, and we have an ideal system.

Also, better designs in pumps, in part inspired by the better understanding of the levels of pressure & flow & pump-heat, and their impacts on a complete system, meant that we started seeing pumps on the market (whether created specifically ala Laing, or sourced from available stock ala Iwaki or Panworld) with more pressure and less peak flow. This aspect was almost critical for bringing the 3/8" and 1/2" worlds closer together. As we added a little bit of extra restriction, the pumps that are well designed can "shrug it off" and continue to plow through the restrictions because their PQ curves are now far more optimally balanced for the PC water-cooling scenario than the pumps we used to have.

The DDC's have best efficiency points (BEP's) within the 4-6LPM range. The "ideal" system to work with these pumps would have a single-CPU block design that is fairly flow-agnostic by around 4LPM and offers a level of restriction that results in 5.5-6LPM flow rates in a 1block/1pump/1radiator system. The end-goal for all the blocks in a 1cpu/2gpu/1chipset/1rad system would be 4-4.5LPM flow-rates, with blocks that are specifically designed to be fairly flow-agnostic by that point.

The final piece of the puzzle is the radiators. More modern radiators are now more flow-agnostic. The performance hit of lower flow-rates from smaller ID tubing is reduced over what once used to be.

So, Swiftech's CPU block designs specifically favored the use of 3/8"ID tubing because of their "the fitting is the jet" designs, and where that wasn't the case, the base-plates were thick enough to not care too much. In the meantime, greater knowledge and understanding in the market place has led to a selection of modern off-the-shelf components where the impact of lesser flow-rates is minimalised as well.

There is still room for improvement though. I still don't see any manufacturer taking a fully wholistic approach to a range of products from top to bottom. That's pretty expensive work though, carefully balancing an entire range of products. The impact of modern pumps and radiators makes the task easier though, but it's been a long road of discovery to get to this point. We're not at the end yet, but we're getting closer.

I personally consider the 775 IHS implementation to be completely flawed, and it has caused the market to take a back-wards step to work around it. I know I'm a fairly lonely voice in a market-place of enthusiasts who don't care about how getting better temperatures is achieved, so long as it works, but believe me when I say that things can still get better. It's taken me some while to understand just what the heck was really going on with S775, 'cos believe me, the theory of it assuming a proper mechanical mounting system made no sense. That's just what the problem was though. The mechanics of the situation are wrong, not the block designs that have been pushed to the wayside in the march for better performance, and we're currently seeing an artificial "bubble" in the forwards progress of block design as a result.

Well, that's my summary of the history to now...

[ranker]

There is still room for improvement though. I still don't see any manufacturer taking a fully wholistic approach to a range of products from top to bottom. That's pretty expensive work though, carefully balancing an entire range of products. The impact of modern pumps and radiators makes the task easier though, but it's been a long road of discovery to get to this point. We're not at the end yet, but we're getting closer.

How do you see watercooling progress in terms of new technology and capturing a larger audience than your typical pc enthusiast?

I'm interested to know as the gains over the past year have really been minuscule compared to the years before. It's gotten to the point where it's almost 'boring' where manufacturers appear to be focusing more on bling rather than pushing the envelope.

I'm really interested in hearing on what you believe the future of WC to be and how we can get there.

[SiGfever]

With the introduction of the DDC series and the use of Iwaki pumps designs such as the Storm should be optimum with the jet impingement. These pumps have the extra kick to make full use of the jets.

Do you think that a design where the jetting is divided into two distinct areas focused over each core would allow the Storm design to shine again?

[NaeKuh]

Cathar, send me a G7 block. :D

OR better yet, make me an offer. :P


Im really dying to own one of your original pieces. I would seriously love one.

[Cathar]

How do you see watercooling progress in terms of new technology and capturing a larger audience than your typical pc enthusiast?

I'm interested to know as the gains over the past year have really been minuscule compared to the years before. It's gotten to the point where it's almost 'boring' where manufacturers appear to be focusing more on bling rather than pushing the envelope.

I'm really interested in hearing on what you believe the future of WC to be and how we can get there.

Capturing a larger audience eh? Might be a good time to take a look at who makes up the respective audiences, and then look at the impact that the unified platforms (consoles) are making into audience that the pc watercooling market might hope to capture. Microsoft is on a mission to own the non-business home computing market, software AND hardware. What makes you or I a PC enthusiast? As in what is it that we actually used a PC for? I'd be surprised if >95% of the PC enthusiast market wasn't captured in the following 5 reasons: "games, internet, folding/distributed computing, music/video viewing/editing, specialised/business software".

Microsoft is targetting the first 4 of those reasons, and some elements of #5 as well. Make no mistake that as enthusiasts, we're really just a pack of die-hards holding onto a computing concept that is earmarked, if not for eventual total elimination, at least for near-complete marginalisation, some time in the next 10 years at a guess. About the only "friends" we have is the business computing market, and you can be sure that they only care about the cost of the end-systems. A stock PC with a quiet air-cooling is good enough. There's no water-cooling market there, or at least, not while water-cooling costs more than air-cooling.

No, I don't think that the PC water-cooling market will ever really take off for that reason. It's always going to be the realm of the die-hard enthusiasts, because everyone else will either be using a unified hardware/software platform solution (Xbox v4 or 5), or using a PC in an office for business.

As enthusiasts, our solutions don't fit in with an XBox or a business PC. Both those computing types may get water-cooling one day, but it'll be some OEM solution that the enthusiast market has no input in.

Sorry for the bleak crystal ball outlook.

As for pushing forwards within the realm of the enthusiast PC market, it's true that we've come a long way, and the gains still to be had are small. There's not going to be any big gains (with the exceptions of bowed blocks for mechanically flawed socket implementations that are more of an anomaly than anything else).

Pumps - The DDC/DDC+ are fantastic PQ/noise wise, but still some cloud over their reliability. There is still room for an astute competitor to come in with a variable speed 12vdc pump and clean up. The performance gains will, at best, still be less than 0.5C, but a pump with 6-8mH2O peak pressure head, 9-11LPM peak flow, and a BEP in the range of 4-6LPM, and as energy efficient as possible (no more than 25W), small, reliable, quiet, and less than $90US, will basically clean up the PC water-cooling pump market, period. The top-modded Laing DDC2 is oh-so-so-close, but it seems that Laing have been dropping the ball lately to jump the final hurdles to take it to a position of total market dominance. Take a pump like that, add on a "speed dial" like the Laing D5 to allow for switching between 5-25W pumping modes to suit the widest range of setups, and no one would ever need buy a different pump again. Buy one pump, dial in the power required that is in balance with your radiator's cooling power, and done.

Radiators - We are close. Very, very close. We can eke out another 5-10% performance or so in an affordable, marketable format, and we can still do a little more work to make them more flow agnostic. I have ideas on how, but won't share them here in public.

Tubing - fat tubing is a turn-off for many, and it makes it hard to route tubing tightly around motherboards and components without involving a lot of forward thinking, and trade-offs. This is part of the reason why I revisited that concept here. 10-12mm OD tubing, while I'm sure some will disagree out of principle, is about as large as is physically practical. There are some small hurdles to overcome here (what fittings are best, and so on), but to get to a point where people can using 10-12mm OD tubing and easily route it without grief, and not see more than a 0.1C performance difference to 3/4" OD tubing would be the final goal here.

Waterblocks - IHS's are here to stay. Some older designs (mine included) were designed at a time that they had to straddle the opposed duality of bare-die CPU's and IHS-capped CPUs. There are a number of very highly performing designs that have been passed over because the specific physical implementations of the design were not wholly optimised for IHS CPU's alone. The magnitude of this has been freakishly amplified by the mechanically flawed nature of the highly popular S775 CPU's. We can still conceptually do ~4C better (at Tjunction, not Tcase) than what's out there on the market today, but the existing IHS implementation on S775 CPU's is preventing much of that from becoming a reality. In short, we're somewhat stuck in a rut with some less than optimal (but still highly performing - make no mistake) designs until the mechanics of S775 changes. In short, the waterblock design market has been backed into a corner that doesn't allow the better designs to really do their thing.

Beyond that rather vague overview, there's a lot of research that needs to take place to get from where we are now, to the best possible. It's probably best, in a sense, that it still remains a largely enthusiast based marketplace, 'cos its the collective passion for the best that will ultimately drive the for the push for perfection, rather than stagnating in unified design mediocrity.

[ranker]

Hey Cathar,

Thanks for the reply as it was an interesting read. You're bleak outlook on WC'ing is disheartening. The hobby itself has been interesting for the past 3 years. To see that large leaps in terms of performance, ease of use, and reliability are over seems to have sealed the fate for WC'ing itself.

If I'm reading this right, you're stating that there's only a limited amount of performance left to capture. Most enthusiasts will usually demand more and more performance and make the leap to the next level. In time, phase will become cheaper. What would prevent phase cooling from eventually cannibalizing the WC'ing domain?

I'm interested in knowing what you're personally working on (besides stuff for Thermochill) and what you see yourself contributing to the WC scene in the near future. Will we be seeing more Cathar designed waterblocks or will you be focusing on radiators as you were recently?

[HiJon89]

I think there's still room for improvement. Just look at something as simple as air cooling and there are still huge leaps being made. The Ultra 120 Extreme blows away the XP-120 which was king of the hill 2 years ago. I think the future is going to be ultra restrictive blocks and pumps pushing ridiculous amounts of head.

[RickCain]

If I'm reading this right, you're stating that there's only a limited amount of performance left to capture. Most enthusiasts will usually demand more and more performance and make the leap to the next level. In time, phase will become cheaper. What would prevent phase cooling from eventually cannibalizing the WC'ing domain?

OCZ was supposed to enter the phase market with a $300.00 unit but it never materialized. That would have pushed a majority of the watercooling people to phase overnight.

Cathar - wouldn't this be a good time to get your chilled water solution moving forward? That should result in nice gains in watercooling performance.

[nikhsub1]

What would prevent phase cooling from eventually cannibalizing the WC'ing domain?
1 werd. CONDENSATION. Ok, one more word. RELIABILITY. Gee, one more - HEADROOM. Oops, another. GPU's. Meh, a few more? NB, SB, mosfets? RAM? HD's. You can phase all that.

[Burn]

IIRC Stew said a while back that the possibility for a performance increase is quickly becoming impossible, even using silver. Because the die is so small, trying to remove 100+W from such a small package becomes difficult to do better and better, and at some point you reach a ceiling.

[NaeKuh]

welll, theres this concept i kinda wanted to try out. Basically a inline chiller, but not something that would drop major voltage on.

Rad -> TEC chiller -> Cpu

Basically the tec chiller would only be used to knock off 5-6C on water temp b4 it was shot into the CPU. So i figure not a very high voltage TEC would be required to do that.

And since the rad will most likely bring the coolant down to the lowest possible, it makes more sense putting it right in front of the TEC chiller.

Only problem is, how to make the chiller. :P

[MaxxxRacer]

Some interseting info Stew. Glad to see you back on the forums.

I stickied the thread and will be updating the main guide with info found in here when I get some time.

[ranker]

1 werd. CONDENSATION. Ok, one more word. RELIABILITY. Gee, one more - HEADROOM. Oops, another. GPU's. Meh, a few more? NB, SB, mosfets? RAM? HD's. You can phase all that.

The condensation part is definitely a good point, but lets not forget that people use to balk at the idea of mixing water with electronics. I think we really need to get back to the purpose of WC'ing. Does any other component depend on better cooling to get great OC results? Besides the CPU, everything else can't really be OC'ed other than GPU's. In addition, GPU's are typically volt limited rather than temp limited.

The same argument you make against Phase have been said during the early days of WC'ing. Most people were just happy to have WC'ed the CPU. People began to speculate about GPU's only to have the naysayers say it was impractical and ineffective. Fast forward years later and now we have people like me WC'ing everything that has a waterblock made for it and then some. Instead of truly focusing on the important aspects of WC'ing, manufacturers have begun to "accessorize" the hobby by making blocks for mosfets, chipsets, HD's, etc and other stuff. It seems as if progress in general is headed towards bling rather than performance as I've stated.

If phase is the future, I can see manufacturers developing something that might be "expandable" to be able to cool multiple blocks. I'm not sure how it would work but possibly the size of the unit itself might shrink to the size of a say a PA120.3. Once the size and price point are lowered, I can see multiple phase "loops" being run within a PC.

As an engineering grad, for someone to say it's impossible or impractical is usually a challenge and not a final answer.

However with that said, I'm hoping that there's still room left for WC'ing to grow and evolve. It's disheartening to have read the past few posts by Cathar and really drives home how bored I've been getting with the hobby in general. I was hoping for a shining light at the end of the tunnel.

[HiJon89]

Does anything else depend on cooling to get great OC results? Besides the CPU, everything else can't really be OC'ed other than GPU's.
Well high FSB does overclock the NB in a way. And at high FSB, watercooling the NB can become essential to maxing out the CPU clocks. (I'm still a little dubious about the SB and mosfet blocks :p: )


For the most part, GPU's are volt limited rather than temp limited.
And after you volt-mod the cards and kick up the voltage, they're right back to being temp limited :D

[Grinch]

Well high FSB does overclock the NB in a way. And at high FSB, watercooling the NB can become essential to maxing out the CPU clocks. (I'm still a little dubious about the SB and mosfet blocks :p: )


And after you volt-mod the cards and kick up the voltage, they're right back to being temp limited :D


good points..:up:

[afireinside]

I will walk through walls of fire for a 1 degree change in temperature. If it were not for my wife, I would run the room airconditioner in my personal study (a small room with a 12,000 BTU wall unit!! ) in the middle of winter where it is -5 degrees F outside, just for that extra lower load temps.

Man your stuff better come pretty damn fast at stock to need a 12k BTU AC to keep it cool...

[sick_g4m3r]

Its never ever over!! Ever!! Muahaha. Truly it wont be. Thats like saying the gasoline engine was over as soon as it was made.


And that TEC Chiller sounds like a good idea. maybe a 45.6W TEC sandwiched between an HSF and a maze-like copper block.

cooling the copper block which cools the water with a lot of contact from the maze-like block. Might work

[Grinch]

it seems like I am upgrading every 2-4 months...not including cases..LOL

[Cathar]

Do you think that a design where the jetting is divided into two distinct areas focused over each core would allow the Storm design to shine again?

There's nothing wrong with the Storm design even now. It focuses on cooling a central patch, and that is exactly what it should be doing.

The "problem" is that the S775 CPU's mechanical mounting characteristics results in less pressure being applied at the center of the IHS between the die and the water-block, and so what instead occurs is that the heat from the die instead spreads out more over the entire IHS, rather than remaining centralised above, which is completely opposed to how the Storm does its job.

i.e. the problem is a mechanical socket issue, not a waterblock design issue.

Now, the mechanical socket issue can be addressed in two ways.

1) Increase the size of the cooling patch to cool the entire IHS. The impingement aspect of the Storm design is better per unit area than the mini-pin designs. I know this to be true (in my own testing - others may disagree) based on bare-die performances. Since the mechnical flaws of the IHS-core mating spreads the heat out over a larger area than the existing Storm implementation is designed to handle, the solution is to expand the cooling patch size.

2) Create a way in which we can properly sandwich the IHS between the die and the block base with a high amount of pressure. One (ugly) solution is to bow the bases. Another solution that I believe would work well is to machine a 22x22mmx0.5mm high step into the middle of the baseplate of the block. On a Storm block this would be achieved by milling away the baseplate by 0.5mm around a central 22x22mm square, a bit like how some GPU blocks are, where they have that raised middle portion to fit inside the shim. This still wouldn't cover the entire IHS, but it'd apply pressure in a manner that would ensure that the IHS gets sandwiched with strong force between the actual die and the wb base. This raised section would also be mostly covered by the Storm's cooling patch. This would be how it would be easiest to modify an existing Storm block to be competitive again on an S775 CPU, and bring the cooling patch design back to where it expects the heat-load to be.

Doing #2 would "fix" the current Storm for single-die (dual core) S775 CPU's.

Doing #1 would fix the Storm to a point where it'd compete, or even outperform, once again anything else with an unbowed base.

Doing both of the above would "fix" the Storm design for quad-core (dual-die) CPU's (but with a 26x26mm raised section instead).

[migueld]

There was a time where the Storm was seen as the absolute best block. The general consensus at the time was that water-block design had reached its peak, and that performance wouldn't get any better, at least not significantly, not even with the mythical silver storm..... anyone remember those days?

Just when the situation seems hopeless some Fuzion thing comes out and blows everyone out of the water. It defies the "laws" of the days, it's several times less restrictive, and several degrees cooler.

I say as long as we don't get clouded by the old and are willing to consider the unknown, there's plenty of universe left for exploration ;)

[Cathar]

There are always engineering reasons for why things are the way they are, or why things changed from what was expected. The true way forwards is through scientific analysis, understanding, modification and refinement. Not romance.

[migueld]

There are always engineering reasons for why things are the way they are, or why things changed from what was expected. The true way forwards is through scientific analysis, understanding, modification and refinement. Not romance.

Sure, just don't get too comfy with equations. Romance may actually give some interesting ideas :p:

[Cathar]

Or just be a way to make money off the gullible (http://www.thesecret.tv/).

[LogAn'sRun]

Or just be a way to make money off the gullible (http://www.thesecret.tv/).

uh thanks cathar, and i had just finished my breakfast. . .

[dinos22]

Stew
what sort of liquid do you use....and do you use any additives to prevent jets from blocking?

[Cathar]

Stew
what sort of liquid do you use....and do you use any additives to prevent jets from blocking?

Filtered tap water. No additives. Have a silver block which acts as a natural biocide. Never had any issues for 30 months straight now with the exact same water that I stuck in all that time ago (I have a reservoir). The same system had a G5 in it before, and now a G7. The odd time I've opened up the blocks up they've been as clean as new. Not one single jet has ever been blocked, and this is even on a G7 which has ~1/50" (~0.5mm) diameter jets (i.e. ~40&#37; of the orifice size of a regular Storm that most people know).

Seriously, it's the additives that most people stick in that causes blockages. Clean your system's components out correctly at the beginning, filter your water, and use a natural biocide (aren't silver blocks nice? :) ), and there's never a problem.

The "worst" problem I have is that my tubing has gone slightly cloudy, but it's still translucent.

[sc00p]

(aren't silver blocks nice? :) ), and there's never a problem.Actually that brought to my mind the only reason why I would ever use reservoir. I could drop a silver coin bottom to the res :D Thanks for the idea Cathar :p:

[MaxxxRacer]

There are always engineering reasons for why things are the way they are, or why things changed from what was expected. The true way forwards is through scientific analysis, understanding, modification and refinement. Not romance.

But I like romance . It solves all problems. I swear it does!

[septim]

hmm do we hear wedding bells soon....

[JargonGR]

Actually that brought to my mind the only reason why I would ever use reservoir. I could drop a silver coin bottom to the res :D Thanks for the idea Cathar :p:

I am doing this in my 3 loop system using silver wire in each or my reservoirs and 3-4 months not the tubes are clean. As Cathar said my only problem is that tubes go a bit cloudy but he water on the Reservoirs is still transparent.
I am not using any additives just pure medical (and cheap) Water for Injection.

I am wondering if there would be any clouding if we could use (in thery ofc) tubes made of glass. I guess not.

[SiGfever]

I also run two silver wires in my Micro-Res.

When I redo my loop I will leave the CPU circuit 7/16" and do the GPU and NB in 3/8" with the push fittings that Cathar listed from McMaster. I will run another DDC-2 w/Alphacool top mounted to my MM hard drive brackets. Those push connect fittings look very interesting.

I just wish that I had more trust in the DDC series pumps because the size is excellent for case placement.

[gabe]

3/8" ID | 1/2" OD into 1/2" ID push-fittings is ideal


Stew:

I don't have too much time to post right now, so I'll go quick: please investigate minimum pressure specs for push-in fittings. As you know, I have tremendous experience with these, and I didn't give them up commercially without solid reasons..

Negatives in a nutshell:
Safety
- push-in fittings were designed for applications where pressure is <2-7> bars. They were never intended for low pressure environments.
- If you are going to use vinyl tubing and push-ins be aware that over time the tube seriously indents at the o-ring level, resulting in reduced o-ring compression and poor seal -think of the effect of a bend in the tubing at proximity of the fitting opening with an under specs seal! Furthemore tolerances in vinyl tubing OD often exceed those of most push-in fitting brands.
Other considerations:
- great to install, horrible to remove for the inexperienced
- expensive


Final consideration: In an extended use scenario, vinyl tubing is counter-indicated due to its high porosity. Alternative low porosity tubing does not work well with push-ins (in our application) for multiple reasons e.g.: hard tubing like polyethylene has low bend radius, and soft tubing like norprene is too soft for adequate seal.

Final final: the reduced pressure drop benefit offered by push-in fittings is incremental at best. Convenience of utilization for trained users prone to install/uninstall frequently is priceless. But they have lost MY vote of confidence for long term/no maintenance systems at this point.


Other than that, thanks for the thorough survey!

[migueld]

Gabe thanks for the information, your experience with push-in fittings is greatly appreciated.

I guess if there will be a shift in fitting usage it might have to be the compression type.

[Cathar]

Thank you very much for the valuable insight Gabe, especially from one with long-term experience with such fittings.

In your experience, does the use of the tubing brace inserts with soft-walled tubing alleviate the stated issues to a significant degree? Much of what you stated seemed to focus around the use of tubing without inserts. Forgive me if I misunderstood. The inserts offer far less of a restriction hit than barbed fittings, and I can easily remodel the impact of using inserts with push-fits.

[gabe]

Thank you very much for the valuable insight Gabe, especially from one with long-term experience with such fittings.

In your experience, does the use of the tubing brace inserts with soft-walled tubing alleviate the stated issues to a significant degree? Much of what you stated seemed to focus around the use of tubing without inserts. Forgive me if I misunderstood. The inserts offer far less of a restriction hit than barbed fittings, and I can easily remodel the impact of using inserts with push-fits.

Tube inserts are mandatory use with vinyl tubing. I wouldn't even dream about installing vinyl in push-in fittings without them. So I am confirming that my observations are with tube inserts.

One thing that helps is to use a locking clip. It clips on the collet, effectively keeping it in the out position. Gives a little more support to the tube and reduce lateral pressure on the o-ring. But still, these fittings are working out-of-specs in our environment.

I am curious: Why concern yourself with a .125" reduction over a few inches when you just demonstrated that the same reduction over several feet in a typical cooling loop is only affecting temps by a mere ~1C ???

Push-ins are elegant and attractive to our kind, but in my experience they represent a possible hazard unless one refills/maintains the system every 6 months to a year.

Don't get me wrong: I still use push-ins in industrial apps where system pressure is 45~60 PSI. In such apps, they are absolutely flawless. Just not in your typical PC cooling system.

[Cathar]

I am curious: Why concern yourself with a .125" reduction over a few inches when you just demonstrated that the same reduction over several feet in a typical cooling loop is only affecting temps by a mere ~1C ???


'cos sudden contractions of 0.125" are significantly more expensive (PD wise) than some run of tubing length of equal diameter. Compare the modelled 8mm over barbs to the modelled 8mm with push-fits.

The goal (well, my goal) is to find a solution that uses the thinnest possible tubing that offer no performance impact greater than ~0.2-0.3C over a 1/2" barbed solution. A 1C difference is unacceptable to me, but that's just my choice. Others have their own preferences for what's acceptable.

Perhaps soft tubing stretched over compression fitting orifices may be the other viable solution?

[gabe]

The goal (well, my goal) is to find a solution that uses the thinnest possible tubing that offer no performance impact greater than ~0.2-0.3C over a 1/2" barbed solution. A 1C difference is unacceptable to me, but that's just my choice. Others have their own preferences for what's acceptable.

Just watch your fluid levels often, is all I can say.

[Cathar]

Just watch your fluid levels often, is all I can say.

Agreed. My personal preference is for no thinner than 3/32" walls (or 2.5mm), for just that reason. Also helps for turning radius too. I didn't state that in my OP though, but I am aware of tubing evaporation/porosity issues, and turning radius issues, for thin walled tubing.

[Top Nurse]

I think all the negatives about push-fits can be summed up as a size thing. These types of fittings have been successfully used in a wide variety of uses in water cooling by European manufacturers though they aren't typically using the sizes that have been discussed here (12mm). I can see that the bigger the OD of the tube the more there is a torsional force at play that could conceivably cause a leak. In my Legris fittings the tubes go in a long ways so there would have to be a severe side stress for them to leak.

In my Aqua Computer manuals they all explain exactly how to connect these types of fitting. They also stress that you should cut off approximately 2mm of the tube every time you remove and reinsert the tube for security purposes.

[Top Nurse]

Perhaps soft tubing stretched over compression fitting orifices may be the other viable solution?

I tried that approach and it is somewhat problematic as the screw down ring is specifically made for a specific size tube. I did get it to work, but I had to use a lathe to get the nuts ID opened up.

[mukmaster]

Very nice guide !!!
Easy Simple Effective

[LogAn'sRun]

Top Nurse, do you have pics of your rig somewhere so I could look at those fittings?

[sbrehm72255]

She has a work log over at the [H], but last I checked, it still hasn't been finished.

[Halk]

She's got 2 worklogs going. There's Feeding Frenzy and there's Feeding Frenzy Interlude. They're both great reading, with good pictures.

[RickCain]

Top Nurse, do you have pics of your rig somewhere so I could look at those fittings?

You would have to visit her work logs on [H] but here is a picture of the push to fits she talks about.

http://i7.photobucket.com/albums/y255/rickcain/Computer%20Stuff/IMG_5308.jpg

[LogAn'sRun]

thanks, is that 8mmID tubing or 10mmid??

[RickCain]

that is 6mm id / 8mm od

[elfy]

damn that's some thin tubing

[LogAn'sRun]

looks sweet, finally I see a good pic of push fits! I'd liked to get 10id if poss. . .

[pie_uk]

so bascially i can safely move to 3/8 tygon now without getting hissed and booed?

lol

[gabe]

Agreed. My personal preference is for no thinner than 3/32" walls (or 2.5mm), for just that reason. Also helps for turning radius too. I didn't state that in my OP though, but I am aware of tubing evaporation/porosity issues, and turning radius issues, for thin walled tubing.


I understand Stew. Please also appreciate that thru this conversation I am also addressing the members of this forum. People need to clearly understand how to use push-in fittings, and the way things go, my warning will be lost and push-ins will become the new thing to do, which more often than not ends up on my lap as in "why don't you make a block with built-in push-ins Gabe".. Been there, done that.. You know what I mean?

So let me be clear one more time (OK call me senile): Push-ins are not designed for low pressure environments. If you use them, be prepared to watch fluid levels often.

BTW Happy Father's Day to all the Dad's in this forum..

[RickCain]

I understand Stew. Please also appreciate that thru this conversation I am also addressing the members of this forum. People need to clearly understand how to use push-in fittings, and the way things go, my warning will be lost and push-ins will become the new thing to do, which more often than not ends up on my lap as in "why don't you make a block with built-in push-ins Gabe".. Been there, done that.. You know what I mean?

So let me be clear one more time (OK call me senile): Push-ins are not designed for low pressure environments. If you use them, be prepared to watch fluid levels often.

BTW Happy Father's Day to all the Dad's on this forum..

I agree with your concern and have tried thinner walled 8mm tubing only to find depending on where the tubing is on the roll, you could have problems (ie. the tubing doesn't stay round towards the end of a roll). It has caused a fair share of problems with leaking for me and have learned to adjust accordingly. The worst thing a user can do it to try and re-use an existing connection without trimming the tubing prior to reinserting.

I have a feeling the challenge will be finding 10mm id push to fit connectors that will work with these blocks having the inlet and outlet holes so close together.

[Cyprio]

I tried that approach and it is somewhat problematic as the screw down ring is specifically made for a specific size tube. I did get it to work, but I had to use a lathe to get the nuts ID opened up.

Hmmm... i guess that's what i need to do with my fittings to get them to close fully.

10mm OD compression fittings with 10 mm nut, using Tygon 1/4" ID, 3/8"OD:

http://www.lubzny.org/Images/Buildpics/fitting.jpg

http://www.lubzny.org/Images/Buildpics/fitting2.jpg

I think Alphacool produce an 11mm nut. Maybe that will help?

[ranker]

so bascially i can safely move to 3/8 tygon now without getting hissed and booed?

lol

Nah. 3/8" isn't bad but any lower and you'll start seeing marked changes in temps. Like Cathar pointed out, the difference between 1/2" to 3/8" isn't that bad and sees 3/8" as the sweet spot.

Just choose between either 1/2", 7/16" or 3/8" to do whatever suits your needs best.

[Top Nurse]

Top Nurse, do you have pics of your rig somewhere so I could look at those fittings?

Well the [H] is down now, but here are some pics. In the first pic I have used a bulkhead connector to run tubing through the middle compartment plate. That's the one in the back. The big one in the front I cut apart and used it as a bushing to run the PSU loom through.




http://i12.photobucket.com/albums/a225/TopNurse/AquatubeHD5.jpg




This was one of my early attempts. Now there are no 90's in this area at all.




http://i12.photobucket.com/albums/a225/TopNurse/AquaTubeUpSideDown_5.jpg




Here you can see a 90 that was used to go through the middle plate and a 45 that went to the CPU.




http://i12.photobucket.com/albums/a225/TopNurse/Back_Power_Hole_5.jpg




Here's a closeup of the Cuplex XT with a pair of 45's. As Cathar pointed out a silver block is nice in keeping the biologicals down the natural way (poison them) :clap:




http://i12.photobucket.com/albums/a225/TopNurse/CPUMount3.jpg




http://i12.photobucket.com/albums/a225/TopNurse/CPUMount6.jpg



Here's the other side of the CPU loop.




http://i12.photobucket.com/albums/a225/TopNurse/CPU_PSU8.jpg




Different types of fittings.




http://i12.photobucket.com/albums/a225/TopNurse/Fittings2.jpg




http://i12.photobucket.com/albums/a225/TopNurse/FeedingFrenzyside1.jpg




Here's where I had to get creative with the Koolance compression fittings because the Koolance tubing is designed to fit 9mm OD and my tubing was 8mm OD. Had a friend make me some prototype nuts.




http://i12.photobucket.com/albums/a225/TopNurse/KoolHD1.jpg


If your interested in seeing the rest of it is on the [H]. Feeding Frenzy Interlude is almost finished. Feeding Frenzy is awaiting some new parts. ;)

[sick_g4m3r]

^ TOPnurse, thats a ton of 90s!!

Your flow must be stand still dead.

[Grinch]

lol

[Top Nurse]

Nah. 3/8" isn't bad but any lower and you'll start seeing marked changes in temps. Like Cathar pointed out, the difference between 1/2" to 3/8" isn't that bad and sees 3/8" as the sweet spot.

Just choose between either 1/2", 7/16" or 3/8" to do whatever suits your needs best.

Perhaps you might want to re-read the first post and take a gander at the pretty pics. ;) Actually he sees the sweet spot at 5/16" (8mm) ID because the 5/16" with a push-fit has essentially the same graph as a 3/8" with a hose barb. And in actuality the difference between the worst and the best is only a measly 1.11 C. I don't think a 1.11 C difference is going to change much in the real world.




For the various tubing/fitting sizes, the PQ curves for a full system for each tubing type looks like this:

http://www.employees.org/~slf/curves/pumps/tubings.png

I overlaid the curves onto the PQ graph for the Laing DDC1+

Okay, the more astute of you will point out that the block C/W is really the case-to-block C/W, and that the actual CPU-die-to-block C/W is a lot higher. Even if we triple block the C/W (which would be an absolute upper limit based upon older research), we get:

6.35mm quick fit = 50.11C
8mm barbed = 49.74C
8mm quick fit = 49.31
9.6mm barbed = 49.25C
9.6mm quick fit = 49.04C
11.1mm barbed = 49.01C
12.7mm barbed = 49.00C

I'll leave it to everyone's own personal value based judgement to determine the relative importance of the differences seen....

It's certainly not the 5C figure that people bandy about. I never expected that it ever would be myself. In my own testing with arbitrarily choking the flow-rate in a test-system, I've always been amazed at the low flow resilience of many setups. Below 2LPM is where things start getting pear shaped quickly for most systems. My recommendation is that even if you're a low-flow fanatic, always ensure that your flow-rates are above 2LPM at the very least, and preferably above 3LPM if at all possible. Still, even when given 1/4" tubing installed with quick-fits and a decent pump like a DDC2, we can see that flow-rates in excess of 4LPM aren't a problem.

[Grinch]

Perhaps you might want to re-read the first post and take a gander at the pretty pics. ;) Actually he sees the sweet spot at 5/16" (8mm) ID because the 5/16" with a push-fit has essentially the same graph as a 3/8" with a hose barb. And in actuality the difference between the worst and the best is only a measly 1.11 C. I don't think a 1.11 C difference is going to change much in the real world.






Kaaa aaa kkkks



very true..:up:

[ranker]

Perhaps you might want to re-read the first post and take a gander at the pretty pics. ;) Actually he sees the sweet spot at 5/16" (8mm) ID because the 5/16" with a push-fit has essentially the same graph as a 3/8" with a hose barb. And in actuality the difference between the worst and the best is only a measly 1.11 C. I don't think a 1.11 C difference is going to change much in the real world.

Kaaa aaa kkkks

Don't try to lie about he stated:

3/8" ID | 1/2" OD into 1/2" ID push-fittings is ideal

Those are his exact words. He sees 3/8" as the sweet spot and only to use 5/16" when you must for bends.

You may not value 1C, nor performance (which is obvious from your full Aqua Computer build), but most of us over here in XS are performance oriented. Many would pay a lot more for that extra 1.11C performance benefit. There's a reason why many of us jumped from 3/8 to 1/2 a few years ago and that was due to the 1.0C gain seen at the time. So yes, 1C is a big jump, which is why most of the WC'ing enthusiasts (people here at XS) purchase thermochill, Laing, Swiftech, D-Tek, etc products.

3/8" tubing itself results in minor .01C performance loss over 1/2" tubing, hence most of us won't mind dropping in size. However, low flow system, irrespective of tubing size, will perform worse. Low flow does not perform as well as high flow. You're using his data as a rallying cry for low flow systems as seen in your other posts; trying to misinform others by applying the 3/8" inch findings towards low flow setups in general.

How about you also stop trying to apply the tubing size findings to restriction overall. Elbows add restriction which hurts performance. More restriction leads to worse temps: http://www.xtremesystems.org/forums/showpost.php?p=2256551&postcount=36

(sigh)

I'll pull out ye olde racetrack analogy.

If I'm a molecule of water, circulating around a water-cooling loop, I'm just going around and around and around. It's just like being a race-car on a race-track at a fixed speed. The time I take to travel through the radiator is like the time spent travelling down the main straight of the race-track.

If the race-track is 5 miles long, of which the main-straight (radiator) is 1 mile long, in the space of 1 hour, how much time per hour do I spend on the main-straight if I'm travelling at a fixed speed of 60mph, 120mph, or 180mph?

The answer is that the speed doesn't matter of course. I spent 1/5th of my time on the main straight. 'cos the straight is 1 mile long out of 5. Even if I travel at twice the speed around the circuit, it'll take me half the time to get from the start to the end of the main straight, but because I'm going twice as fast everywhere else, I'll be on the main-straight twice as often. i.e. No matter how fast I travel, I'll be on the main-straight for 12 minutes out of every hour.

Now common physics tells us that the rate of heat-exchange is proportional to the temperature difference between an object, and something else that's cooler than the object. If I'm a molecule of water, and air is cooling me (by way of the air cooling the metal tubes inside the radiator that I'm flowing through), then the longer I spend in the radiator, the cooler I will get (that's good), BUT, the cooler and closer I get to the air-temperature, the less quickly I'll lose heat (that's bad). The two cancel each other out. So why does higher flow results in better performance?

The more quickly I rush around, the more likely I'm going to be tumbled about (think white-water rapids as opposed to a smooth slowly flowing river). This means that I'm going to get tossed against the cool metal walls of the radiator more often, rather than just cruising along down the middle of the tube, only passing heat slowly to water molecules beside me that are only a little cooler than I, because they are beside another molecule, and then beside another molecule, before we get to the cold metal wall. i.e. water sucks for transferring heat if it's not getting mixed about and thrown against the cold walls.

Hope that explains it in a "simple" manner that is intuitive, obvious, and directly counters the "slower flow is better" argument.

You want as much flow as possible to dissipate heat better within the radiator.

[sick_g4m3r]

Is it possible to get 8mm ID tubing in the US?

EDIT: nvm i like the 3/8" QF, thats the sweetest spot

[Top Nurse]

Is it possible to get 8mm ID tubing in the US?

EDIT: nvm i like the 3/8" QF, thats the sweetest spot

There are quite a few places you can get the stuff. McMaster-Carr has all kinds of metric and inch tubing available at the click of your mouse. Please keep in mind the shore hardness of the tubing so you get appropriate tubing as specified by Legris. IIRC, most of the push-fit fittings I have gotten from them are Legris brand. You can purview their requirements at www.legris.com

[LogAn'sRun]

Agreed. My personal preference is for no thinner than 3/32" walls (or 2.5mm), for just that reason. Also helps for turning radius too. I didn't state that in my OP though. . .


Not to be picky, but THAT is actually what he said later on; which wouldn't be the 3/8"ID 1/2"OD, it would be slightly larger. But this is just nit-picking right? :rolleyes:

[Methylphenidate]

I've actually always wondered about the impact of using a 1/2" loop with a 3/8" segment leading right into the CPU block. For something like a D-tek FuZion, it seems to me that you'd get the benefit of relatively free flowing 1/2" tubing for most of your loop, but with an impingement effect directly over the die of the CPU.... Just an idle thought i had. I may actually test it at some point.

[Top Nurse]

Not to be picky, but THAT is actually what he said later on; which wouldn't be the 3/8"ID 1/2"OD, it would be slightly larger. But this is just nit-picking right? :rolleyes:

The choice of wall thickness has to do mainly with turning radius. The larger the wall thickness the less problems with making sharp bends and having the tube collapse. I think someone else also mentioned less problems with transfer of coolant through the tubing wall. I believe that was what Cathar was discussing when he wanted a 8mm ID with a 12.x OD.

In my use of 6mm x 8mm tubing you have to be careful what kind of tubing you use as mentioned by R1ckCa1n. Actually I was the one who encouraged Sharka to get the Mazzer PUR tubing due to it's higher flexibility. The test sample that was sent worked very well with push-fits. Unfortunately the roll of production tubing shipped was wound very tight on a small roll and it malformed the tubing in such a way that negated the use of it in a push-fit environment. The stuff AC sells (have no idea what their supplier is, but suspect it is Legris) is a PUR with a limited bend radius and a shore hardness that makes it ideal for its intended application.

[Top Nurse]

^ TOPnurse, thats a ton of 90s!!

Your flow must be stand still dead.

Actually not. :D

I know using 90's is a no no, but perhaps this is also a size thing as well where it affects more negatively in a higher flow environment. My current loop (Feeding Frenzy Interlude) has a bunch of 90's and 45's and my current flow is sitting around 165 LPH. If I were to ditch the restrictive flow meter I think it would go up to about 200 - 225 LPH, but then I wouldn't know. ;)

[C'DaleRider]

Don't try to lie about he stated:


Those are his exact words. He sees 3/8" as the sweet spot and only to use 5/16" when you must for bends.

You may not value 1C, nor performance (which is obvious from your full Aqua Computer build), but most of us over here in XS are performance oriented. Many would pay a lot more for that extra 1.11C performance benefit. There's a reason why many of us jumped from 3/8 to 1/2 a few years ago and that was due to the 1.0C gain seen at the time. So yes, 1C is a big jump, which is why most of the WC'ing enthusiasts (people here at XS) purchase thermochill, Laing, Swiftech, D-Tek, etc products.

3/8" tubing itself results in minor .01C performance loss over 1/2" tubing, hence most of us won't mind dropping in size. However, low flow system, irrespective of tubing size, will perform worse. Low flow does not perform as well as high flow. You're using his data as a rallying cry for low flow systems as seen in your other posts; trying to misinform others by applying the 3/8" inch findings towards low flow setups in general.

How about you also stop trying to apply the tubing size findings to restriction overall. Elbows add restriction which hurts performance. More restriction leads to worse temps: http://www.xtremesystems.org/forums/showpost.php?p=2256551&postcount=36


You want as much flow as possible to dissipate heat better within the radiator.

To further Cathar's analogy on tumbling vs. smooth flow of fluid through a radiator.....you can see a real world application in aftermarket transmission and oil coolers. Hayden, Perma-Cool, among others, incorporate within the tubes of their upper line add-on coolers, a system to tumble, or "turbulate" as they call it, the fluid. The swirling and tumbling of the fluid enhances the cooling effect of the coolers as more fluid is exposed to the tubes. So, very slow, low flow systems that ooze the coolant through the radiator are typically not as efficient in cooling as a swifter moving stream of coolant would be....just as Cather noted.

Of course, then there is the laminar flow problem that is likely increased as flow decreases. This only makes sense as the path of least resistance becomes the center of the tube as flow decreases......it is much easier for water/coolant molecules to stick to the tube's sides....henc emore flow is toward the center of the tube.

Granted, most of my experience with laminar flow problems is in the medical field.....in critical care areas (emergency room, trauma and life flight, cardiovascular and open-heart surgical recovery and critical care), but the same set of physics surely is in play within water/coolant tubing as is within the cardiovascular system in the body......just to a little lesser degree (red blood cells and platelets tend to be "sticker" than water molecules.)


I've found this thread fascinating....the immense amount of theory and information on radiator and tubing considerations is a fascinating read. Thanks for the continuing flood of information.


J.M., RN, BSN, CCRN, CEN, CFRN, TNS

[C'DaleRider]

The choice of wall thickness has to do mainly with turning radius. The larger the wall thickness the less problems with making sharp bends and having the tube collapse. I think someone else also mentioned less problems with transfer of coolant through the tubing wall. I believe that was what Cathar was discussing when he wanted a 8mm ID with a 12.x OD.



Interesting you mentioned the fluid transfer through the tubing wall. It's not something I've seen a lot of mentioned here, but I'd think it'd be a problem and concern for long-term setups.

I was doing a bit of reading on Saint-Gobain's website (mfgr. of Tygon), which is tygon.com or labpure.com, and the water absorption rates for various formulations of their tubing is listed.....but you have to dig for it.

For instance, Tygon 3603, a very popular tubing here, has an absorption rate of water of 0.24&#37; (figure represents percentage of water absorbed in 24 hours at 23C.)

Tygon F-4040-A, a fuel line formulation, has a permeation rate of 0.49%.

Tygon B-44-3, beverage tubing, has a rate of 0.13%.

Tygon B-44-4X, a food, milk, dairy tube, has a rate of 0.15%.

Tygon LFL, long flex life tubing, has a rate of 0.18%.

Tygon Silver antimicrobial, the best at rejecting water absorption amongst Tygon tubing that has a working psi range of at least 20psi (I rejected any tubing rated for less than a 20psi working pressure), has an absorption rate of <0.01%.


The water absorption rates were not dependent on tubing thickness but were only a property of the tubing compounding, obviously. So naturally, the thicker the walls of the tubing, the slower the effects of water absorption would be to show. But it seems to me, given everything else being fairly equal, that the lowest absorbing tubing should be in consideration as tubing to be used.

Granted, Tygon Silver isn't equal with other formulations of Tygon or other tubing....its bend radius isn't the best @ 1 1/2" for the 3/8"ID-1/2"OD tubing, but it has other properties going for it. One, obviously, is the antimicrobial property. Another is its higher resistance to alcohols than other Tygon PVC-based tubing.

It is, unfortunately, a little stiffer with a Durometer rating of 72 vs. the 55 of the 3603, but I don't know if that is significant enough to be that much of a difference.


I also wonder if the use or exclusion of plasticizers on the inner wall of the various tubing choices available to us has any effect on its durability, longevity, and any other effects plasticizers may play in a cooling loop. Or does it make any difference at all? Can plasticizers leech out of the tubing and eventually coat the working parts of, say, a cpu or gpu block? Or is this not a real concern at all?

Thanks for the info!!!


J.M., RN, BSN, CCRN, CEN, CFRN, TNS

[qdemn7]

Stew, I want to say thank you very much for your work. this makes me fell much better since i had been planning to install Colder NSH QD couplings (http://uscorp.thomasnet.com/viewitems/tubing-hose-colder-products/nsh-series-couplings?&sortid=40&measuresortid=0) for their flow rate. However they're rather expensive. It seems like the QD coupling that McMaster-Carr sells would work as well. Page 174.

[bito]

I have a bunch of John Guest Quick fit fittings/inserts here, all different sizes, from my old Swiftech days......now i have a use for them again !!

[Concorde Rules]

Nice work BUT it seems you didn't test in real world conditions!?

Things on paper rarely work out as they do in RL :P

Hell of a lot more testing, but would show once and for all the difference :/

[Marci]

He outlined the components necessary in the OP, used Realworld data for the various parameters... it's up to the endusers to test the theory out in RW conditions. Anyone with a rig matching the original specification can check it all out by repiping from their current to any suggested tubing in the OP and validate their results against the theoretical results.

Rig Spec:


Laing DDC1+ (unmodified)
Thermochill PA120.2 with 2 x Yate-Loon fans at 12v
Swiftech Apogee GTX
Conroe C2D CPU, overclocked and under load, emitting 100W of heat
2 meters of tubing length

Change current tubing over to any of the suggested (other than current, obviously)


6.35 (1/4") ID tubing with quick-fit fittings
8mm (5/16") ID tubing over 6mmID|8mmOD barbs
8mm (5/16") ID tubing with quick-fit fittings
9.6mm (3/8") ID tubing over 7.5mmID|3/8"OD barbs
9.6mm (3/8") ID tubing with quick-fit fittings
11.1mm (7/16") ID tubing stretched over 10.5mmID|1/2"OD barbs
12.7mm (1/2") ID tubing over 10.5mmID|1/2"OD barbs

Then validate against


Final CPU temperature is ambient (22C) + system load (114W) * radiator C/W + CPU Load (100W) * block C/W

The final CPU temperatures work out to be:

6.35mm quick fit = 34.21C
8mm barbed = 34.08C
8mm quick fit = 33.91C
9.6mm barbed = 33.89C
9.6mm quick fit = 33.80C
11.1mm barbed = 33.79C
12.7mm barbed = 33.77C

Can't expect Cathar to do ALL the work - he's given everyone the foundation to decide for themselves, and the necessary info to validate for themselves (obviously, account for change in ambient if one exists)... time will provide the realworld-condition tests.

[gabe]

Interesting you mentioned the fluid transfer through the tubing wall. It's not something I've seen a lot of mentioned here, but I'd think it'd be a problem and concern for long-term setups.

I was doing a bit of reading on Saint-Gobain's website (mfgr. of Tygon), which is tygon.com or labpure.com, and the water absorption rates for various formulations of their tubing is listed.....but you have to dig for it.



Definition:
ASTM D570-98(2005)
Title: Standard Test Method for Water Absorption of Plastics
This test method covers the determination of the relative rate of absorption of water by plastics when immersed. This test method is intended to apply to the testing of all types of plastics, including cast, hot-molded, and cold-molded resinous products, and both homogeneous and laminated plastics in rod and tube form and in sheets 0.13 mm [0.005 in.] or greater in thickness

Water Absorbtion rate is NOT the information you are seeking.

Permeation rate is the relevant info, also called the WVTR or Water Vapor Transmission rate, and it is usually measured in Grams per mil thickness per 100 sq inches per 24 hours at 73F, 50&#37; relative humidity.

Definition:
WVTR (water vapor transmission rate) is the steady state rate at which water vapor permeates through a film at specified conditions of temperature and relative humidity. Values are expressed in g/100 in2/24 hr in US standard units and g/m2/24 hr in metric (or SI) units.

This info is not usually published by tubing manufacturers, and only available upon request. We spent close to year gathering the data, to come up with the tubing that had the lowest permeation rate for low maintenance (no refills) applications, and came up with another StGobain product called Norprene, which is used in our Quiet Power P180 chassis.

I am the one who mentionned permeation issues to Stew (Cathar) because this type of tubing doesn't work properly with push-in fittings. Given that we are actively working on reducing maintenance (among other things), use of low permeation tubing is therefore critical to us.

[ranker]

Definition:
ASTM D570-98(2005)
Title: Standard Test Method for Water Absorption of Plastics
This test method covers the determination of the relative rate of absorption of water by plastics when immersed. This test method is intended to apply to the testing of all types of plastics, including cast, hot-molded, and cold-molded resinous products, and both homogeneous and laminated plastics in rod and tube form and in sheets 0.13 mm [0.005 in.] or greater in thickness

Water Absorbtion rate is NOT the information you are seeking.

Permeation rate is the relevant info, also called the WVTR or Water Vapor Transmission rate, and it is usually measured in Grams per mil thickness per 100 sq inches per 24 hours at 73F, 50% relative humidity.

Definition:
WVTR (water vapor transmission rate) is the steady state rate at which water vapor permeates through a film at specified conditions of temperature and relative humidity. Values are expressed in g/100 in2/24 hr in US standard units and g/m2/24 hr in metric (or SI) units.

This info is not usually published by tubing manufacturers, and only available upon request. We spent close to year gathering the data, to come up with the tubing that had the lowest permeation rate for low maintenance (no refills) applications, and came up with another StGobain product called Norprene, which is used in our Quiet Power P180 chassis.

I am the one who mentionned permeation issues to Stew (Cathar) because this type of tubing doesn't work properly with push-in fittings. Given that we are actively working on reducing maintenance (among other things), use of low permeation tubing is therefore critical to us.

Hey Gabe,

Would you happen to know the permeation rate of the more popular brands of Tygon or have a link handy?

[_G_]

So let me be clear one more time (OK call me senile): Push-ins are not designed for low pressure environments. If you use them, be prepared to watch fluid levels often.

BTW Happy Father's Day to all the Dad's in this forum..

when you mention low pressure does that include the vacuum that forms on the suction side of a powerful pump?

[gabe]

when you mention low pressure does that include the vacuum that forms on the suction side of a powerful pump?

excellent observation, yes it does. this is were vinyl tubing will want to collapse over time unless it is reinforced.

[gabe]

Hey Gabe,

Would you happen to know the permeation rate of the more popular brands of Tygon or have a link handy?

As I mentionned above, this data is not published by manufacturers, and you need direct access to factory engineers to get it.

According to the data we have gathered here, PVC formulations (without liners) are at an average WVTR of 5~6 times that of Norprene which is given for 0.83 g mil/100in^2 day, and silicon formulations (without liners) are up to 20x.

[ranker]

As I mentionned above, this data is not published by manufacturers, and you need direct access to factory engineers to get it.

According to the data we have gathered here, PVC formulations (without liners) are at an average WVTR of 5~6 times that of Norprene which is given for 0.83 g mil/100in^2 day, and silicon formulations (without liners) are up to 20x.

Thanks for the response. I'm assuming that St. G won't be answering any emails directly to an end user about this so the info is definitely appreciated.

What are some of the commercial names of the Noprene tubing you've talked about and most importantly does mcmaster carry them?

[C'DaleRider]

Gabe, the water absorption rates I posted for the various Tygon tubing were done by this standard, according to their .pdf files of the various tubings I listed from Saint-Gobain's website:

ATSM D570 for the Tygon Silver, Tygon B-44-4X, Tygon F-4040

ATSM D570-81 for the Tygon LFL,

ATSM D570-98 for the Tygon R3603


So, I think the water absorption, as Saint-Gobain put it in their .pdf's, is indeed the same values you want to know as the permeation rate, or the Water Vapor Transmission Rate......

Now, I do not know what the difference between just ATSM D570, D570-81, and D570-98 are.....maybe you could fill us in?

You mention vacuum resistance......the same .pdf's, again available on Saint-Gobain's website in each tubing's description page, lists these properties for different tubing....


Tygon R-3603....... in 3/8" ID X 5/8" OD..... 29.9" of mercury at 73F.

Smaller tube thicknesses in the 3/8" ID range are lower.




Tygon R-3603 with 7/16" ID X 5/8" OD ...... 15" of mercury at 73F.

7/16" X 11/16" OD ........... 28" of mercury at 73F.



Tygon R-3603 with 1/2" ID X 5/8" OD ..... 5" of mercury at 73F.

1/2" ID X 3/4" OD ...... 21" of mercury at 73F.




Link to Tygon R-3603 specs webpage w/.pdf link for testing specs, measurements, etc. (http://www.tygon.com/Data/Element/Node/ProductLine/product_line_edit.asp?ele_ch_id=L00000000000000014 95)

Link to webpage of all Tygon tubing....lots of interesting variations in Tygon. (http://www.tygon.com/Data/Element/Node/Category/Category_edit.asp?ele_ch_id=C0000000000000001208)

[C'DaleRider]

As I mentionned above, this data is not published by manufacturers, and you need direct access to factory engineers to get it.

According to the data we have gathered here, PVC formulations (without liners) are at an average WVTR of 5~6 times that of Norprene which is given for 0.83 g mil/100in^2 day, and silicon formulations (without liners) are up to 20x.

Actually, if you follow the link in my above posting, the link has a .pdf file you can access that lists exactly the ATSM testing procedure for water permeation (ATSM D570-98 for Tygon R-3603) and value within it. So, while you may not be able to get a response from Saint-Gobain, the info is on their website.

[Top Nurse]

excellent observation, yes it does. this is were vinyl tubing will want to collapse over time unless it is reinforced.

So why not use the tubing that push-fits were designed for and eliminate this whole problem?

[gabe]

So, I think the water absorption, as Saint-Gobain put it in their .pdf's, is indeed the same values you want to know as the permeation rate, or the Water Vapor Transmission Rate......


sorry C'Dale but I have no time to discuss this right now. you are incorrect.

[gabe]

So why not use the tubing that push-fits were designed for and eliminate this whole problem?

polyethylene tubing. .. low bend radius .. hard to work with.

[C'DaleRider]

sorry C'Dale but I have no time to discuss this right now. you are incorrect.

DUH...I finally reread and realize my mistake. Sorry. :doh:

[ranker]

polyethylene tubing. .. low bend radius .. hard to work with.

Seems like a no sure fire win, instead its just different trade offs, for push fits then. I'll be sticking with barbs rather than having to eyeball my water levels consistently.

Thanks for the heads up Gabe. :up:

[Top Nurse]

polyethylene tubing. .. low bend radius .. hard to work with.

I think I'm using polyurethane and it's easy to work with in the sizes I've used (6 x 8 and 8 x 10). They also have fittings available in 45's and 90's if you want to do something peculiar. For instance this would be impossible to do without 90's:




http://i12.photobucket.com/albums/a225/TopNurse/Feeding%20Frenzy%20Interlude/FFI_052.jpg




http://i12.photobucket.com/albums/a225/TopNurse/Feeding%20Frenzy%20Interlude/FF_GPU_2.jpg

[ranker]

I think I'm using polyurethane and it's easy to work with in the sizes I've used (6 x 8 and 8 x 10). They also have fittings available in 45's and 90's if you want to do something peculiar. For instance this would be impossible to do without 90's:




It's at that tubing size that most of us are unwilling to go down to, nor take the hit of adding multiple 90's and 45's to our loops, just for the sole reason of saying you can make it work.

You've made it clear that top notch performance isn't what you're after. I believe Gabe is expressing how it wouldn't be ideal for for the medium/high flow builds. The tubing required for optimal 3/8", 7/16", 1/2" wc'ing builds seems to be too stiff with an atrocious bend radius.

[SiGfever]

The idea was very appealing but it seems that the trade off of convenience to leak rate does not warrant their use.

[_G_]

maybe what is needed is a normal 7/16 barb with a 3/8 id.
Anyone in here have a CNC screw machine laying around?

[dinos22]

i like your setup Top Nurse

:up:

[Cathar]

I'm just feeling that this is all excellent discussion. I can provide the feedback and the theory to demonstrate what the effects are, and it's put it to the wider community to come up with a practical solution to make it all possible. I put forward the idea of push-fits, but it seems that there are issues here that I wasn't aware of. I don't have all the answers and haven't tested everything, yet here we see a wide selection of forum users who were once at each other's throats, combining experience and working together to find a way to arrive at a practical deployable solution.

Really good stuff guys! Keep it up!

[Top Nurse]

maybe what is needed is a normal 7/16 barb with a 3/8 id.
Anyone in here have a CNC screw machine laying around?

You can make simple barbs like this with just a regular screw machine. No CNC needed. Of course you have setup charges to assimilate into the price, but a 500 piece run would certainly be possible.


i like your setup Top Nurse

:up:

Thanks :) The fun is in building them.

[GrimReaperGuy]

Gabe, how does Norprene handle compared to the usual Tygon 3603 we play with? It is less prone to collapsing?

[gabe]

I think I'm using polyurethane and it's easy to work with in the sizes I've used (6 x 8 and 8 x 10).

that will work to (all hard tubes will work), but again, hard to bend.

[gabe]

Gabe, how does Norprene handle compared to the usual Tygon 3603 we play with? It is less prone to collapsing?

we strictly use it in conjunction with smartcoils. it cannot be used alone, as it collapse too easily.

in such configuration, we have excellent bending radius, better than vinyl I'd say.. the only problem of Norprene is that it costs 10x vinyl.

http://www.swiftech.com/assets/images/products/Stealth/Stealth-sli-parallel.jpg

but in my book, peace of mind primes. by the way, we have performed tests on this over extended periods of time: two exact same loops, one with vinyl, and one with norprene running side by side for 10 months now. results validate the specification data. I have upgraded all my systems to Norprene now, servers, etc...

no one probably noticed (or added 2+2) but that's the reason why we claim such low maintenance in the Quiet P180 ;-)

[DarthBeavis]

my wife says small tubing works well but she won't admit she like bigger better cause she knows it just is not available