Short vrs long tube loops

[JeffnWV]

Can some one comment or refer me to a thread on the reasons for ( if any) not having longer tubing loops?
I'm considering setting up another box (custom wooden) for my wc system which would mean another few ft of tubing overall.

[Marci]

It's thermodynamics / fluid dynamics physics... friction. The more tubing, the higher the flow and headloss due to friction.

MANY sites with articles covering it, altho the majority are nonspecific to PC Watercooling.

http://www.google.co.uk/search?q=frictional+losses+water+tubing&ie=utf-8&oe=utf-8&rls=org.mozilla:en-GB:official&client=firefox-a

[IanY]

The concern here is head pressure, which drops with every additional foot of tubing. It depends on what is in the loop and how restrictive the blocks are. It definitely depends on what pump you have. If you have an uber pump, or two of pumps, then discussions aboout pressure loss and flow rate become highly academic (eg, if I were to add 10 pumps in series, would an extra 10 feet of tubing matter? lol). We need to know what pump you have and what is in your loop.

[JeffnWV]

Thx guys,
Ian, I am watching these forums trying to learn and decide what's the best and most effective way to design my system. I haven't decided on a pump yet so recommendations ( which you and others have made already in posts) are welcome ("In the multitude of counselors there is wisdom")
But I want to put my "system" in an other box close to my PC which will mean another 3-4 feet of tubing overall (guessing). so I wondered what the impact would be. I'm looking for a great and stable overclock but the system is going to be a user system and not a benchmarking setup.

[Graystar]

Another 4 feet of tubing won't make a noticable difference unless it's 1/4". If you're using 3/8" you're okay, and if you're using 1/2"...don't even think about it.

[JeffnWV]

thx Graystar, I think I'm decided on the 7/16 tubing route.
The real exciting part is fabricating the dovetailed enclosure(s) I'm picturing in my mind.

[IanY]

Thx guys,
Ian, I am watching these forums trying to learn and decide what's the best and most effective way to design my system. I haven't decided on a pump yet so recommendations ( which you and others have made already in posts) are welcome ("In the multitude of counselors there is wisdom")
But I want to put my "system" in an other box close to my PC which will mean another 3-4 feet of tubing overall (guessing). so I wondered what the impact would be. I'm looking for a great and stable overclock but the system is going to be a user system and not a benchmarking setup.


I speak only for myself, and what I would do and what I like would not necessarily reflect what others would prefer.

I wouldn't lose sleep over 4 feet of extra tubing.

Under normal circumstances, I would not want to run any pump singularly. There are way too many stories of dying pumps. Pumps do not cost a lot of money, not compared to the price of the hardware and the time invested building your labor of love.

Two pumps of anything in series would lay the issue to rest. Actually, it wouldn't blow the doors off one pump, but at least it creates enhanced flow and head pressure.

My standard operating procedure would be to run two pumps in series. That is pretty much what I do with any system that has an aggregate cost above $1000. I have quite a few w/c systems at home.

As to pumps, the most recommended pumps are made by Laing, and the most recommended models are either the DDC+ 18 watts (also known as DDC Ultra and MPC355) or the D5 (also known as the MCP655). The regular DDC+ without an aftermarket modified top is a good performer, but doesn't show its potential unless you buy that extra top. The best modified tops are made by either Petras Tech Shop or Alphacool or Radical. The D5 pump doesn't need a modified top and comes with a screw to turn down the speed (and hence performance) of the pump. Both the DDC+ and the D5 are priced in teh same range at about $70 to $75. The aftermarket top for the DDC+ adds another $20 to $25.

There is a down-scaled DDC 10 watt model that would be good for silent systems but which I suggest that you avoid because of your objective to add an external box.

If you can afford, Dual DDC+ with Petra tops (at about $200) would be fabulous. Run the pumps in series.

If you can spend even more money, there are the esoteric pumps like Iwakis, but don't expect to get away with paying less than $200 for one pump, much less two.

Just remember to do your homework and not trust what any single person says. Get third and fourth opinions. Everyone here puts on their pants one leg at a time and there are no deities here, although there are plenty of God-sized egos.

[Levish]

Why on earth would anyone run 2 iwakis especially if we are talking about md20z or rd30 pumps.

They are both reliable and high performance as well as comparable in price to two ddc+'s with modified tops.

Their biggest drawbacks of the Iwaki's are the size in the case of the md20z and the noise they make and the fact that they are drop shipped (no one stocks them afaik).