The impact of tubing sizes

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Originally Posted by LogAn'sRun

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

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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/y25...f/IMG_5308.jpg

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

that is 6mm id / 8mm od

damn that's some thin tubing

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

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

lol

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Originally Posted by Cathar

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.

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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..

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Originally Posted by gabe

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..

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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.

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Originally Posted by Top Nurse

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.

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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?

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Originally Posted by pie_uk

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

lol

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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.

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Originally Posted by LogAn'sRun

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

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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/a2...quatubeHD5.jpg




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




http://i12.photobucket.com/albums/a2...SideDown_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/a2...wer_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/a2.../CPUMount3.jpg




http://i12.photobucket.com/albums/a2.../CPUMount6.jpg



Here's the other side of the CPU loop.




http://i12.photobucket.com/albums/a2...e/CPU_PSU8.jpg




Different types of fittings.




http://i12.photobucket.com/albums/a2.../Fittings2.jpg




http://i12.photobucket.com/albums/a2...renzyside1.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/a2...se/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. ;)

^ TOPnurse, thats a ton of 90s!!

Your flow must be stand still dead.

lol

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Originally Posted by ranker

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.

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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.

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Originally Posted by Cathar

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.

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Originally Posted by Top Nurse

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

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very true..:up:

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Originally Posted by Top Nurse

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

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Don't try to lie about he stated:

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Originally Posted by Cathar

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

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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/...1&postcount=36

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Originally Posted by Cathar

(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.

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

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

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

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Originally Posted by 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

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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

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Originally Posted by Cathar

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. . .

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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:

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.

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Originally Posted by LogAn'sRun

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:

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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.

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Originally Posted by sick_g4m3r

^ TOPnurse, thats a ton of 90s!!

Your flow must be stand still dead.

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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. ;)

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Originally Posted by ranker

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/...1&postcount=36


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

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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

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Originally Posted by Top Nurse

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.

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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% (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

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 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.

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 !!

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 :/

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:

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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

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

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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

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Then validate against

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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

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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.

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Originally Posted by C'DaleRider

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.

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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.

Quote:

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Originally Posted by gabe

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.

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Hey Gabe,

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

Quote:

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Originally Posted by gabe

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..

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

Quote:

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Originally Posted by _G_

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

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

Quote:

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Originally Posted by ranker

Hey Gabe,

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

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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.

Quote:

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Originally Posted by gabe

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.

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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?

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.

Link to webpage of all Tygon tubing....lots of interesting variations in Tygon.

Quote:

---

Originally Posted by gabe

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.

Quote:

---

Originally Posted by gabe

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?

Quote:

---

Originally Posted by C'DaleRider

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.

Quote:

---

Originally Posted by Top Nurse

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.

Quote:

---

Originally Posted by gabe

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:

Quote:

---

Originally Posted by gabe

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:

Quote:

---

Originally Posted by gabe

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/a2...de/FFI_052.jpg




http://i12.photobucket.com/albums/a2...e/FF_GPU_2.jpg

Quote:

---

Originally Posted by Top Nurse

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.

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

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?

i like your setup Top Nurse

:up:

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!

Quote:

---

Originally Posted by _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?

---

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.

Quote:

---

Originally Posted by dinos22

i like your setup Top Nurse

:up:

---

Thanks :) The fun is in building them.

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

Quote:

---

Originally Posted by Top Nurse

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.

Quote:

---

Originally Posted by GrimReaperGuy

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/image...i-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 ;-)

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

:rofl: :ROTF: :clap:

Quote:

---

Originally Posted by 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

---

Uh, these are the XtremeSystems forums. I think you might be lost. Here's a link back to where your post might be better received. ;)

Quote:

---

Originally Posted by Cathar

Uh, these are the XtremeSystems forums. I think you might be lost. Here's a link back to where your post might be better received. ;)

---

:ROTF: thats great

lolz

Sorry, 4 oz of Jager does it . . .

Quote:

---

Originally Posted by Cathar

Uh, these are the XtremeSystems forums. I think you might be lost. Here's a link back to where your post might be better received. ;)

---

Damn those are some xtreme systems thar . . .

Quote:

---

Originally Posted by Cathar

Uh, these are the XtremeSystems forums. I think you might be lost. Here's a link back to where your post might be better received. ;)

---

http://i12.photobucket.com/albums/a2...yperson7zi.gif

Quote:

---

Originally Posted by Top Nurse

http://i12.photobucket.com/albums/a2...yperson7zi.gif

---

:shocked: :rofl: :ROTF: :yepp: :clap: :up:

doesn't it just make you wonder what cathar does when not posting here...

romance?

Excellent info in this thread!
Took me a while to ream through it, but wsa definately worth it.

Nice to see that the 8/10mm we are using in Germany for ages are not as bad as we think.

Quote:

---

Originally Posted by elfy

doesn't it just make you wonder what cathar does when not posting here...

---

Racing => Hospital => Pain pills => Physical Therapy => Typing on forums => Pain pills => Racing. :D

Quote:

---

Originally Posted by Top Nurse

Racing => Hospital => Pain pills => Physical Therapy => Typing on forums => Pain pills => Racing. :D

---

You forgot the most important one...spending quality time with his kids. :up:

Quote:

---

Originally Posted by Fr3ak

Nice to see that the 8/10mm we are using in Germany for ages are not as bad as we think.

---

Today it's not that bad due to improvements in the rest of the water cooling equipment, but it was bad before.

Quote:

---

Originally Posted by BRiT

Today it's not that bad due to improvements in the rest of the water cooling equipment, but it was bad before.

---

QFT

This might be a bit off topic, but does anybody have thoughts on 5/16" ID NALGENE tubing? I haven't found 5/16" ID Masterkleer or Tygon, but I've found Nalgene tubing in town. By the way, the stuff I found is 5/16" ID 1/8" Wall 9/16" OD. Almost as large as the Masterkleer. Of course, just holding it here, no Smartcoils and no liquid inside, it's definitely making the one-inch bend radius using my hands.

Quote:

---

Originally Posted by MotF Bane

This might be a bit off topic, but does anybody have thoughts on 5/16" ID NALGENE tubing? I haven't found 5/16" ID Masterkleer or Tygon, but I've found Nalgene tubing in town. By the way, the stuff I found is 5/16" ID 1/8" Wall 9/16" OD. Almost as large as the Masterkleer. Of course, just holding it here, no Smartcoils and no liquid inside, it's definitely making the one-inch bend radius using my hands.

---

I think that Gabe mentioned this recently. Why not do a search for posts on his name?

Quote:

---

Originally Posted by Top Nurse

I think that Gabe mentioned this recently. Why not do a search for posts on his name?

---

He mentioned Norprene, not Nalgene. Also, Nalgene is PVC, he keeps mentioning polyethylene.

Quote:

---

Originally Posted by MotF Bane

He mentioned Norprene, not Nalgene. Also, Nalgene is PVC, he keeps mentioning polyethylene.

---

Sorry. :shrug:

Okay, so we accept that the suction side of the pump is a bad place to be installing a quick-fitting. I'm assuming that this is where the bulk (all?) leaks occur?

Would a viable solution be to plumb all positive pressure routes in the system with quick-fits, and the final section into the pump which is subject to negative pressure with regular barbs?

Would that provide an amenable work-around? Pumps do like to have minimal restriction leading into them too, so a system that was all 3/8", but for the final run into the pump, use a 1/2" ID tubing section over barbs there.

Just thinking along he lines of horses for courses. Use quick-fits where it's suitable to use them, and use barbs for the small sections where they are more appropriate.

Never seen a leak there before, but the elbow push-fits I use are the rotating style so you can point it in the direction you want. Not to be confused with the ones that are used in industrial robots that move constantly. But I also would probably put the pump somewhere else next time where it isn't so close to the case walls after what I have read here just to see if there was a difference.

If the pump is pumping constantly and there is no air in the system why would it matter about the size going into the pump?

Quote:

---

Originally Posted by Cathar

Okay, so we accept that the suction side of the pump is a bad place to be installing a quick-fitting. I'm assuming that this is where the bulk (all?) leaks occur?

Would a viable solution be to plumb all positive pressure routes in the system with quick-fits, and the final section into the pump which is subject to negative pressure with regular barbs?

Would that provide an amenable work-around? Pumps do like to have minimal restriction leading into them too, so a system that was all 3/8", but for the final run into the pump, use a 1/2" ID tubing section over barbs there.

---

That's similar to the setup I had in QPower cases using a long 1/2" tube from res. to MCP600 pump inlet, and a short 1/2 to 3/8 reduction at the pump outlet feeding the blocks (with built-in QC fittings) and what have you.

similar to this, but with the res instead of the fill-and-bleed:

http://www.swiftech.com/assets/image...lic630x590.jpg

except that you'd still have to work a little more on the return section (CPU or Rad to Res)

Quote:

---

Originally Posted by _G_

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

---

Quote:

---

Originally Posted by Cathar

Okay, so we accept that the suction side of the pump is a bad place to be installing a quick-fitting. I'm assuming that this is where the bulk (all?) leaks occur?

---

With the amount of headpressure pumps have, I don't think there's actually a vacuum at the suction side of a pump. All the pump does, is overcome a pressure difference. The actual lowest pressure (at the suction side of a pump) might still be 2 ft (just an assumption). (if pressure would be 0 ft at suction side, the thing won't work)

This ofcourse doesn't mean that push fittings at these locations are ok to use, I'm only wondering at what amount of head pressure it's not wise to use push fittings anymore.
Is 2 ft too low, is 5 ft good enough? The head pressure will drop as soon as it leaves the pump, maybe it's not wise to use push fittings when it reaches the second block in the loop.
Experience (of others) says they do work though, and sometimes they leak.

Quote:

---

Originally Posted by spookmineer

With the amount of headpressure pumps have, I don't think there's actually a vacuum at the suction side of a pump.

---

Ok, if we're being pedantic, there's pressure that is less than atmospheric pressure before the pump inlet, causing the atmosphere to push in and attempt to crush the tubing.

There have been numerous posts from various people where they've shown that with soft-walled tubing, all you need to do is to slightly restrict the run into the pump inlet and the tubing will collapse. Sticking a restrictive block before the pump inlet will achieve the same effect.

If you don't believe me, I'll set up a test and video it in effect for you, using a DDC-2. Believe me, it happens.

When my Storm rev2 became partially clogged the 7/16"id x 5/8"od Tygon R-3603 tubing at the DDC-2 inlet started showing signs of reduced diameter. I cleaned the block and then put 1/2"id Tygon R-3603 between the Micro-Res and the pump inlet. I mentioned this occurence to nikhsub1.

Edit: Old Timer's was kickin in again...DDC-2 :yepp:

Quote:

---

Originally Posted by Cathar

Ok, if we're being pedantic, there's pressure that is less than atmospheric pressure before the pump inlet, causing the atmosphere to push in and attempt to crush the tubing.

There have been numerous posts from various people where they've shown that with soft-walled tubing, all you need to do is to slightly restrict the run into the pump inlet and the tubing will collapse. Sticking a restrictive block before the pump inlet will achieve the same effect.

If you don't believe me, I'll set up a test and video it in effect for you, using a DDC-2. Believe me, it happens.

---

It wasn't meant to be pedantic...

Thanks for the explanation. I don't have a watercooling setup (yet) but your post is very plausible, no need for a video.

If anything, my post was to question at how much head pressure there could be a problem, as quick fittings don't (potentially) cause problems just before the pump, but even before this:

Quote:

---

Originally Posted by spookmineer

I'm only wondering at what amount of head pressure it's not wise to use push fittings anymore.
Is 2 ft too low, is 5 ft good enough?

---

[edit]
I hope I'm correct here, 1 bar equals 10.2 meter of water pressure (= 33.46 feet).
I guess manufacturers give out specs of overpressure? Assuming that's the case, then people who experience collapsing tubes are having more pressure loss through their loop then the specs given by manufacturers... (going below 1 bar)
Their loop is more restrictive then the pressure from specs can handle, and the pump intake is indeed below 1 bar.

Or Gabe's explanation is the cause of the problems with push fittings:

Quote:

---

Originally Posted by gabe

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.

---

[/edit]

Quote:

---

Originally Posted by spookmineer

With the amount of headpressure pumps have, I don't think there's actually a vacuum at the suction side of a pump.

---

There is a depression at the pump inlet, this is a fact, an observation if you will, not an opinion, and not debatable.

This depression causes vinyl tubing to collapse over time upstream of the pump inlet. This is also a fact, an observation, not an opinion thus not debatable either.

A solution to prevent tube from collapsing is smartcoils, but this does not address the sealing issue in quick connects.

Quick connects are only designed to work under positive pressure as specified earlier. The depression causes seal failure. Air will engulf at the seal. This is also an observation, not an opinion. Please take my word literally: I have OBSERVED this phenomenon in many systems from customers, employees, and my very own.

Please learn from my mistakes.

Quote:

---

Originally Posted by gabe

There is a depression at the pump inlet, this is a fact, an observation if you will, not an opinion, and not debatable.

---

I stand corrected (my assumption "The actual lowest pressure (at the suction side of a pump) might still be 2 ft" was false).
But I did not say there wasn't a depression at the pump inlet, I said it isn't a vacuum... ("going below 1 bar" is not the same as a vacuum).

In other words, "Their loop is more restrictive then the pressure from specs can handle, and the pump intake is indeed below 1 bar." is not an exception but it goes for all systems?
Or does depression simply mean, the location in the loop with the least amount of head pressure, but still more then 1 bar?

Quote:

---

Originally Posted by gabe

This depression causes vinyl tubing to collapse over time upstream of the pump inlet. This is also a fact, an observation, not an opinion thus not debatable either.

---

...? In a way, you are repeating my quote of you :confused:

Quote:

---

Originally Posted by gabe

Quick connects are only designed to work under positive pressure as specified earlier. The depression causes seal failure. Air will engulf at the seal. This is also an observation, not an opinion. Please take my word literally: I have OBSERVED this phenomenon in many systems from customers, employees, and my very own.

Please learn from my mistakes.

---

I believe you! If push-in fittings were designed for applications where pressure is <2-7> bars, it has no place in hardly any watercooling system (it needs 66 feet of head pressure??), with most pumps the push fittings would work below system specs.

Somehow I get the feeling my post is misread, I can't see where I am arguing/denying with anything you posted.

After reading a lot of threads (here and elsewhere) I still know almost nothing about this subject. I'm just curious about it, and perhaps annoyingly so. :(

Quote:

---

Originally Posted by spookmineer

I'm just curious about it, and perhaps annoyingly so. :(

---

it is a very good thing to be curious :-) yes I am mildly ennoyed -in fact concerned would be more accurate a description, concerned that ppl are not getting the message accross.. but don't worry it's curable with a good glass of wine!

First off Cathra your quit a guy . I am glad to see you finely straightened this miss out. I have been A small tube guy myself for ever when it comes to pc's . Many of us took endless flaming for our stance that small tubing was = to large tubing. As you illustrated so well each has its place and it does infact have everthing to do with components used in the entire loop.

Since so many listen to you I wish you would go over once more the differances between running 2 pumps in series vs. 2 pumps in parallel .

Parallel when talking about pumps is so much superior to series thats its almost laughable anyone who would argue the point of serial being superior in the world of pc usage. Needs to be straightened out also seems to me Cathra is the man for that job.

Quote:

---

Originally Posted by Top Nurse

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.

---

TN I agree with what Cartha has shown here but your taking what he said and has shown. Way out of context . Everthing Carths has shown us is loop dependent. With all the 90's your using you have infact a very restrictive system that doesn't meet the spec's of Cartha and the temp variations that he showed would in know way apply to your system as shown. Now if you used copper tubing with straight fitting and nice 90degree bends I would agree with you . I have linked sources were you can buy these fitting . I suspect tho . Now that cats out of bag you will be able to buy in PC shops shortly.

Quote:

---

Originally Posted by Turtle 1

Parallel when talking about pumps is so much superior to series thats its almost laughable anyone who would argue the point of serial being superior in the world of pc usage. Needs to be straightened out also seems to me Cathra is the man for that job.

---

Before I launch into it, and I have covered it in the past, may I first enquire as to which two pumps you had put together in parallel, and against what sort of system restriction, that leads you to make that statement with such conviction?

Is it possible to use 7/16'' barbs and stretch the 3/8' tubing over them? That should yield flow close to that of using quick-fits right?

Ok I can do that for ya.

I use 2 differant sets ups for this. One set up uses RD30 single pump .
2x. Alphacool AP1510 outlet to y block 2 1/2 inletts and 1 3/4 out let . this go to 4 160's that have been modded to 3/4 id tubing . From the last 160 tubing goes to this part on the inlet side.
http://www.emiplastics.com/water_regulators2.htm

I use both the WO98 or the WO99 . The W099 is intended to be used with skulltrail when released.

From the flow control out let we run a 3/4 tube back to another y Block than the 2 1/2 " lines go to inlets of the 2 pumps to end the 6 loop set up.

Of course with the RD30 no y blocks are used. Both pump set up flow around 8gpm.

Okay, so if I understood that right, the only real source of restriction you have in the system are the PA160's radiators?

In that instance, yes, pumps in parallel would be significantly better in very low restriction setups like the one you just described.

For a full system though, with a waterblock offering some measure of real restriction, things rapidly start to favor pumps in serial.

For example: Apogee GTX, PA120.2, 2 x Laing DDC with PTS tops

My apologies to the colour blind:

http://www.employees.org/~slf/curves...ube-serpar.png

In all cases, pumps in series win. The reason is because of the waterblock. Notice how the series and parallel pump lines intersect at 11LPM (~3gpm). i.e. if your flow rates are above 3gpm, then having the pumps in parallel would be better (for that particular pair of pumps).

My mitake I use the RD 20 . Been toying with use of rd 3o because it has the flow i want 10gpm but it also has some thing i really don't want. Added noise but the use of 2 allows me 10GPM witch I want . Dave just told me I made mistakes above as 2 RD20 are required and y blocks are in fact used sorry about that . But we preferr the Alphacool pumps as their more versatile for our use thats the plus . The minus is they require more room thats the - . Insid the lian li caseits not a problem as far as space is concerned, As we completely redid the cas interior to fit our needs . As well as the face plate and side panels.

Quote:

---

Originally Posted by Cathar

Okay, so if I understood that right, the only real source of restriction you have in the system are the PA160's radiators?

In that instance, yes, pumps in parallel would be significantly better in very low restriction setups like the one you just described.

For a full system though, with a waterblock offering some measure of real restriction, things rapidly start to favor pumps in serial.

For example: Apogee GTX, PA120.2, 2 x Laing DDC with PTS tops

My apologies to the colour blind:

http://www.employees.org/~slf/curves...ube-serpar.png

In all cases, pumps in series win. The reason is because of the waterblock. Notice how the series and parallel pump lines intersect at 11LPM (~3gpm). i.e. if your flow rates are above 3gpm, then having the pumps in parallel would be better (for that particular pair of pumps).

---

Thanks so very much for your time. Dave is here helping me now so as not to screw up again . Dave said there is only one part that he has ever used that would cause alarms to go off if someone put a system together using the wrong parts. He says you are responsible for that part . The storm he says congrats on a great part design.
But thats part isn't used in the high flow system . We have our own part for that now.

Dave said that inorder to get 8 gpm flow and use parts that turn off and on with the PC he has to run 2 pumps in parallel to achieve this he is not happy with the noise but we have gotten rid of most of it to the point its just a slit hum . but 2 RD 20 are noiser and 2 rd30 are worse .
Hopefully someone will come out with a better hi flow pump.

Some questioned the correctness of old beliefs. Here's an analysis on an old-school system.

The system we're comparing is a DangerDen Maze 4, an Eheim 1048 or Eheim 1250, and a Thermochill HE120.2 with some decent fans on board. ~4 years ago, this was a high performance system in the USA.

Interactive flow-performance results, on an 80W mildly overclocked CPU of the same era may be found here.

The HE120.2 radiator performance curve can be found here. We'll be using the pink curve to represent the fans, which would be about the full-time tolerable noise limit for many individuals.

We'll be assuming a 120W CPU heat load though, which was more typical of the high-end overclockers of the day. Pump heat dump is ~10W for the 1250, and 5W for the 1048.

The flow rates between 3/8" and 1/2" are seen on this graph:

http://www.employees.org/~slf/curves/pumps/m4.png

For the 1048:

3/8" => 4.8LPM
1/2" => 6.9LPM

For the 1250:

3/8" => 6.2LPM
1/2" => 9.6LPM

Looking to our Procooling graph, and multiplying the values by 1.5 (120/80), we get:

1048 1/2" to 3/8" delta => 1.4C
1250 1/2" to 3/8" delta => 1.8C

The estimated radiator water temperatures are:

For the E1048:
125W @ 4.8LPM => 5.4C
125W @ 6.9LPM => 5.2C
=> 0.2C delta

For the E1250:
130W @ 6.2LPM => 5.5C
130W @ 9.6LPM => 5.2C
=> 0.3C delta

With lower speed fans, the radiator performance deltas get slightly larger.

So the total delta for 3/8" tubing with barbs to 1/2" tubing with barbs is:

1048 => 1.9C
1250 => 2.1C

Those were the differences for just moving from 3/8" to 1/2", for the really heavy overclockers. Obviously that is what justified the move for many.

Like I've said for those who were wondering why things are different nowadays. Things have changed. Water-cooling has evolved.

Quote:

---

Originally Posted by Cathar

Some questioned the correctness of old beliefs. Here's an analysis on an old-school system.

The system we're comparing is a DangerDen Maze 4, an Eheim 1048 or Eheim 1250, and a Thermochill HE120.2 with some decent fans on board. ~4 years ago, this was a high performance system in the USA.

Interactive flow-performance results, on an 80W mildly overclocked CPU of the same era may be found here.

The HE120.2 radiator performance curve can be found here. We'll be using the pink curve to represent the fans, which would be about the full-time tolerable noise limit for many individuals.

We'll be assuming a 120W CPU heat load though, which was more typical of the high-end overclockers of the day. Pump heat dump is ~10W for the 1250, and 5W for the 1048.

The flow rates between 3/8" and 1/2" are seen on this graph:

http://www.employees.org/~slf/curves/pumps/m4.png

For the 1048:

3/8" => 4.8LPM
1/2" => 6.9LPM

For the 1250:

3/8" => 6.2LPM
1/2" => 9.6LPM

Looking to our Procooling graph, and multiplying the values by 1.5 (120/80), we get:

1048 1/2" to 3/8" delta => 1.4C
1250 1/2" to 3/8" delta => 1.8C

The estimated radiator water temperatures are:

For the E1048:
125W @ 4.8LPM => 5.4C
125W @ 6.9LPM => 5.2C
=> 0.2C delta

For the E1250:
130W @ 6.2LPM => 5.5C
130W @ 9.6LPM => 5.2C
=> 0.3C delta

With lower speed fans, the radiator performance deltas get slightly larger.

So the total delta for 3/8" tubing with barbs to 1/2" tubing with barbs is:

1048 => 1.9C
1250 => 2.1C

Those were the differences for just moving from 3/8" to 1/2", for the really heavy overclockers. Obviously that is what justified the move for many.

Like I've said for those who were wondering why things are different nowadays. Things have changed. Water-cooling has evolved.

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I think most of us here at XS grasp the concept and understood how things have evolved and changed.

However, I feel sorry for the fight you're getting over on [H]. Seems like they're a little slow and trying to deliberately spin your results into championing how low-flow setups have been superior all along. (For those that are interested in seeing what happens when you anger the natives: http://www.hardforum.com/showthread....1200495&page=3)

I'm sure most people here at XS will appreciate this graph as it helps demonstrate your conclusions by allowing us to compare how it applied back then and how it applies to today's water cooling components.

I don't like the natives, I'm happy right here. . . .

:weapon:

:CTF:

:cord:

Quote:

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Originally Posted by ranker

However, I feel sorry for the fight you're getting over on [H]. Seems like they're a little slow and trying to deliberately spin your results into championing how low-flow setups have been superior all along. (For those that are interested in seeing what happens when you anger the natives: http://www.hardforum.com/showthread....1200495&page=3)

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Would that be considering angering the natives, or being intelligent in the proximity of a troll home?

Excellent findings!

Quote:

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Originally Posted by MotF Bane

Would that be considering angering the natives, or being intelligent in the proximity of a troll home?

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Being intelligent in a proximity of a troll home for sure.

Quote:

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Originally Posted by ranker

Being intelligent in a proximity of a troll home for sure.

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You linking to another forum and your comments could be considered trolling too......

But hey, anything to keep the flaming right? :down:

Quote:

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Originally Posted by RickCain

You linking to another forum and your comments could be considered trolling too......

But hey, anything to keep the flaming right? :down:

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Heh so true, that's pure flamming/trolling. It's sad :p:

Quote:

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Originally Posted by RickCain

You linking to another forum and your comments could be considered trolling too......

But hey, anything to keep the flaming right? :down:

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Quote:

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Originally Posted by migueld

Heh so true, that's pure flamming/trolling. It's sad :p:

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Hi Pot, Meet Kettle, You're black too. :)

If anything I was thanking Cathar for posting his results so it could be more easily understood/referenced during discussions and pointed out that he wasn't so lucky to receive the same reception at another forum.

Considering that Cathar has probably forgotten more about water cooling than most of us will ever know who cares what the uninformed think? :shrug: