DIY Watercooling project - pointers needed

Hi folks...
So i was walking to work and i came across a scrap metal shop...
I thought, 'hey, it wouldn't kill me if i take a look around'. And then the ghetto watercooling bug stung me and I got myself two copper blocks 120x90x20mm for $1,20 and a dual heatercore for $25...nice deal, huh?
I'm only lacking a pump, tubing, barbs, clamps, retention for the wblock -i'll build it out of plexiglas-,shroud, and a res -tupperware?-.

Is it ok if the fins on the heatercore are alu? I guess that won't suffer from galvanization/corrosion cause of the copper sink/pipe...

The other doubts i have are regarding the pump and waterblock design.
I'll be machining the block/s myself, and i thought i could cross drill it easily and have a block for my cpu first.
Would it be better if i made sort of a pin pattern carved onto one side of each block and then sandwich them together?
Or perhaps build two blocks with one carved side and add a plexiglas cover with holes for nipples. Suggestions?

Then, the pump...If i get a cheap submersible one how should i mount it in my loop? I'm not quite sure on how to hook the different parts of my setup.

Thanks in advance!

ps: i won't use axial fans btw...i'll use a car dual blower shrouded on top of the hcore pulling air out and upwards (and the rad will lie besides my case, out in the cold) Oh, and i plan on cooling just my cpu -and perhaps NB on my ancient P4 rig -maybe i'll add a peltier to chill the water next...

This has a lot of text and I apologize

That sounds like something I'm doing, actually....


I built my first computer over the summer in anticipation of senior project. I'm also custom designing the case, as well as the water cooling system. You teach a puppy to swim by throwing him in the river, right? Haha.

But my setup... (TL;DR warning, skip to the bottom unless you want to read my ideas for my setup, also, I apologize if I ramble...which might be a little too late now)

I've got 14"x14" square wooden platform, with two sides. The reason I'm using wood is because wood is a lot easier to cut them plexi, or galvanized steel. I have a CRAP TON of galv steel from ANCIENT computers I scavv'd off of friends and family, haha. The mobo is placed on the platform, then I plan to cut 3" long by 1" wide slats on the two wooden sides, for air intakes. I'm going to use the mesh like you see on screen doors to keep TOO much dust from getting inside.

The front and back of it are going to be made of plexiglass (I really wanted Lexan, it's more durable and easier to work with, not to mention, it doesn't DISSOLVE like acrylic when alcohol touches it, plus acrylic plexi is about twice as fragile as Lexan) and I'm going to have them so they are easy removable. The motherboard will be on a platform that slides, so whenever I need to maintenance the computer I can just slide it out, like a desk drawer. (My dad's absolutely genius idea)

On the top of the box...will be a flat top. There will be a single hole in the middle, just the right size for a 140mm fan. This fan will be a 5500RPM, 243CFM Delta. It will pull in air from the slats on the side of the computer, and blow air over a radiator (a copper[the best kind] heater coil from an '85 Ford Bronco) that will cool the entire computer. I've got about 30feet of 1/8" copper tubing from two old refrigerators that I found junked. I'm making the water blocks by cutting up sections of the copper tubing and then using a blowtorch and a hammer to turn them into solid (mostly) water blocks. Then I'm going to drill holes in them one way or another so they work well as a water block. The copper tubes will come out the top of the box and then go into the reservoir, where a water pump will pump the hot water right into the heater coil, and then out again once it's cool. The reservoir will sit beside the heater coil, or it might surround it in a U or square shape, to serve as a bit of a shroud so the Delta can work even better. ;D

BUTYEAH. That's the idea I got for my build. But since you read all that, (or didn't), on to sharing the useful info I've found.

Copper has a conductivity rating of something like .823 or near there. Aluminum, on the other hand has a rating of around.... .300. A higher rating is better, and as you can see, Cu is a MUCH better conductor. And using copper tubing, water blocks, and radiator make for a very efficient (and non-corroding) setup. Also copper is just a tad more resistant to "punctures" then plastic is. However it does require a bit more love to get it to work right. I have an outside fish pond water pump, one of those that's designed to shoot water 2 feet in the air. It's also....about 4 inches long and 2 inches tall. It's a compact, quiet, and powerful little pump. ;D I'll post again later with what kind of brand it is. (not at home) Thankfully, I got all of these parts for free, courtesy of my father, and his tendency to gather strangely useful things. But if you are forced to use a copper/aluminum setup make sure you use an anti-corroding agent, otherwise the mixture of copper/aluminum/distilled water will DESTROY the aluminum in mere days. Provided water is going 24/7.

Dye in general is a bad idea, though I imagine since I'm using a pump designed for outdoor use, I could put just about anything I darn well pleased in it. If you MUST use plastic tubing, buy Primoflex. An old forum thread here, or on overclock.net had a user who bought Tygon, Primoflex, and the other brand...and primoflex was the most flexible, whereas Tygon was the most durable.

So sorry for the text wall megalong post. But uh, just ask if you have any more concerns. After my weeks of research and webcrawling I'm a veritable sponge of water-cooling knowledge. Just ask here, or PM, whichever you desire.

Once again, sorry for text wall.

The fins of the rad being alu do not matter from a corrosion standpoint so long as the body are all copper alloys. $25 for a heatercore isnt the greatest deal but sufficient.

Now down to business, how were you planning to drill the holes in the copper for your cross drilling? If its a bench press then you really should consider picking up a 2 axis cross slide vise. That will effectively convert your drill press into a make shift table mill. I did that back in the day before I had money for decent tools(around 2002).

Cross drilled blocks really don't perform that technique is so 2001... Really what your looking for is high surface area, and a thin base. If you can't come up with a way to horizontal machine the blocks a plunge method could be utilized to achieve similar results.

As far as internal designs go aim for no more than 3/16" of base material with a preference for 1/8" the closer you can get the water to the cpu the faster it can take the heat out. Keep in mind flow restriction but you do want alot of surface contact. I will say though that one of the best performing blocks I ever made had a simple design. Using a 1/4" bit I cut a cavity .3" deep into a half inch stock measuring 45x45mm, the inlet was directly over the middle and the outlet was on the corner across from it. The only inside channel features where a single .2" thick elbow ~20x20mm. This forced the water to flow onto the center of the core to the other side of the block and then around to the back where the outlet was. A very simple high flow design that I found particularly effective.

Of course alternatively to that the classic maze pattern is fairly simple to machine as well and can give pretty decent performance.

As to the heater core just build an acrylic/mdf fan shroud and duct tape it onto the HC and attach as many of the largest fans you can fit onto it(120,140,180mm) the higher RPM fans are going to be your best bet with a heater core.

DIY Watercooling

Hey guys! Thanks a lot for the info...I've been away for a few days and couldn't answer.
The guy i bought the HC from actually knew a friend of mine -who happened to be there chatting with him when i was picking more stuff up (small world, huh?)- so i can get as many scrap parts i may need from him for free.

Back to the block design...I don't have proper tools so i may have to borrow some from a tool-shop or pay someone to machine them for me. I think i'll try to make a really thin base with the inlet in the middle, outlet in one corner and the maze pattern carved on one of the copper blocks and then weld a copper top to it and attach barbs to it. The tubing i'm not too concerned atm, gotta figure out how to build the block first.
Also, i'm selling my old rig to buy some new stuff...it's gonna take some time to gather the new cpu, mobo, gpu, ram and psu, so i'm in no hurry with the cooling.

Romantic, that project of yours sounds rather ambitious! Keep us posted on that

Oh, BTW... ssjwizard, so your saying that i won't have corrosion if the fins are alu and the pipes/water block are Cu?
I can get a whole copper heatercore if that's not the case for free...no worries

The fins do not come into contact with the circulating fluid so there is no way for electrolysis to occur.

ivanlabrie said:

Hey guys! Thanks a lot for the info...I've been away for a few days and couldn't answer.
The guy i bought the HC from actually knew a friend of mine -who happened to be there chatting with him when i was picking more stuff up (small world, huh?)- so i can get as many scrap parts i may need from him for free.

Back to the block design...I don't have proper tools so i may have to borrow some from a tool-shop or pay someone to machine them for me. I think i'll try to make a really thin base with the inlet in the middle, outlet in one corner and the maze pattern carved on one of the copper blocks and then weld a copper top to it and attach barbs to it. The tubing i'm not too concerned atm, gotta figure out how to build the block first.
Also, i'm selling my old rig to buy some new stuff...it's gonna take some time to gather the new cpu, mobo, gpu, ram and psu, so i'm in no hurry with the cooling.

Romantic, that project of yours sounds rather ambitious! Keep us posted on that

Oh, BTW... ssjwizard, so your saying that i won't have corrosion if the fins are alu and the pipes/water block are Cu?
I can get a whole copper heatercore if that's not the case for free...no worries

Click to expand...

You should get the whole copper core. Copper fins (though expensive) will help cool a lot better then aluminum. Though as long as the inside of the rad is pure copper, and your water blocks or any other metal parts are copper, you should be perfectly fine.

Ok, i'll ask my freebies supplier to gather some copper rads for me
I'll post back with my findings.