Noobish watercooling question

[DeathWalking]

I'm planning on building a watercooled computer for the first time, all my other builds having been air cooled. I've put together a list of what seem to be decent components, having read a bunch of other threads to see what people recommended. My question is this: will my loop suffer for using a 3/8" tube on a 1/2" pump?

 

[phreejak]

well, it isn't ideal but why are you using a 1/2 pump with 3/8 ID tubing. Just get the MCP355 - it's the best pump on the market for 3/8 ID cooling loops and it cost about the same as the preferred 1/2 ID pump, the MCP655, and is every bit as powerful.

 

[DeathWalking]

Okay, thanks!

 

[ouch1]

The only other issue I can see with using a 1/2" pump on 3/8" tubing is pressure. Due to the tubing change you will see more pressure than with 1/2" tubing. It might be a good thing, and it might not. But I wonder what the other people around here have to say about that.

-ouch1

 

[Granite3]

Ouch1,

Static pressure gets involved making the transition up and down in size, affects flow rates, and equipment lifespans. Number of turns (more than 90 deg turns) will also add to the pumps load.

These situations are where the quality pumps really kick the cheapies to the curb.

If you need to know what static pressure is, try sucking the air out of an empty 2 liter bottle. Easy at first, but harder till it gets impossible.

 

[ouch1]

Granite,

Have you ever worked on a fuel system? If not please understand that if you take a outlet with a costant pressure of 20PSI and have it neck down to a fitting that is 3/4 the outlet size you will actually increase the pressure by roughly 20% (at least that is the theory). And I was not sure if increasing the pressure would be beneficial to the cooling loop or if it would cause problems. Such as requiring too much force from the pump to keep the coolant moving, or possibly not providing enough coolant to the cpu block for optimal cooling. So was not willing to say a yay or nay about it to him.

BTW here is some correct info on static pressure for you:
http://en.wikipedia.org/wiki/Static_pressure

-ouch1

 

[barthautala]

In cooling situations pressure doesnt aide or hinder performance. Its the flow rate you want to be concerned with.

Imagine a 2 liter bottle with tiny hole poked in the lid. Flip it upside down and squeeze and it takes pretty much forever to drain, very little flow rate but alot of pressure. Youll also notice how hard it is to get the water out.

Now unscrew the lid and flip the bottle upside down and squeeze. The water drains out of the bottle alot faster.

To relate this to your cooling question - the tiny hole is 1/2" fitting. Alot of strain on the pump - not enough water flowing through the system to cool your hot parts.

 

[jonny_ftm]

From what I read (as I'm migrating to WC), phreejak gave a good answer: The MCP355 is the best pump for 3/8 tubing, as it has a much better head than the MCP655. But, as its flow rate is smaller, it will be more suited for short loops: one WB + Radiator.
The real questions are:
- what are you willing to cool, what components you use
- why going with 3/8 tubing? 1/2 tubing will give you more upgrade options for later. Also, you can use 7/16 (hard to find) tubing: same great flow rate as 1/2 but less bulky

Also, better go with the MCP355 with petra's top, as it will give you a much improved flow in the circuit

I'm not a pro, but read much about it recently. others could correct me if I'm wrong

 

[DeathWalking]

Also, better go with the MCP355 with petra's top, as it will give you a much improved flow in the circuit

What's a "petra's top"?

Unrelated question, I recently read something about how mixing copper and aluminum in a loop is a bad thing beacuse of galvanic corrosion. I was planning on setting up a loop with an Apogee GTX (copper) and an EHX-1000BK. Potential problem? Definitely hoping for a response in the negative here, I've already purchased all of my stuff.

 

[jonny_ftm]

http://www.petrastechshop.com/laddcwpeddto.html

Here's the Petra's top

 

[DeathWalking]

Sooo, I'm beginning to panic a little bit. Reading up on this galvanic corrosion business. Umm, even using a good anti-corrosive mixture (I welcome suggestions as to what's good) is a more frequent changing of liquid that 2 times a year for mixed Copper/Aluminum loops recommended?

 

[ryanthesav]

haha why cant u just get 1/2'' tubing its not that much $$$$

 

[ouch1]

DeathWalking,

Just stick to a good quality copper setup to avoid corrosion. Or if you want make sure that any aluminum in the loop has a very high quality power coating or plating of some kind on it (preferably gold). Or if you want just use water wetter in the coolant to minimize the danger of corrosion.

-ouch1

 

[phreejak]

DeathWalking,

DOn't worry so much about the galvanic corrosion issue. It really isn't that big a deal if you use professional coolants and avoid homebrewed coolants. I've been using PC-ICE for over 5 years now. While I have used many different waterblocks over the years, I have been using my Swiftech TEC Waterblock for about 3 and a few other various waterblocks (some of which have been aluminum) and I've not experienced any sort of galvanic corrosion yet.