Planning Custom Cpu block

Hi everyone, so as i was rummaging through the garage i found a nice piece of copper laying around.

Its 63mm long by 44mm wide and it is 5mm thick so here i am staring at this and i suddenly remember that i have a new 400L/hr pond pump that i never used. So adding two and two i thought that that piece of copper would probably make a nice waterblock.

The thing is, using the swiftech apogee gtz as reference, my piece of copper is 6mm shorter on one side and 13mm longer on the other (the apogee being 50mm x 50mm).

I played around in corel and came up with these ideas:



i was thinking of doing a sandwich kind of effect in three layers.

1.The channel is going to be milled 2mm deep into the copper block.
2. A 10mm sheet of acrylic cut all the way through using the same design as the base plate.
3. A 5mm piece of acrylic with just the barb holes sticking through.

Acrylic layers fixed with acrylic glue, then this is attached to the base with silicon glue and screwed together with 6x4mm screws.

so the big questions are, will the size of the base plate be ok?

And will this kind of design work?
I have a friend who can cnc this out of the copper and the acrylic. I was planning to tell him to leave out the final polishing pass so that all the little grooves in the bottom of the copper plate are still rough therefore creating some turbulence (i hope).
One problem i see is that the acrylic may snap on such a thin area (for the separation).
but other than that, am i wrong about this whole design?

comments good and bad welcome as long as they are constructive
Thanks in advance!

 

It all sounds...sound. I would switch the sealant to Permatex auto gasket sealant. I had the silicone seal on Bloo's block leak because bacteria ate through the seal. -Also the silicone was a total b*tch to cure. It took over a week of forcing air through the block to get the glue cured.

 

Ah thanks, i do have some silicone gasket maker but its bright red
I'll have to look around if i can get some transparent stuff or at the very least black.

Also which would you advise? the design with the 2mm separation or the one with the 4mm separation, also does the water flow look ok in these designs?

Ive never done this and as i don't really feel like buying a big bar of copper id like to not mess up with this one if i can help it.

thanks again.

 

They make a copper gasket stuff too.
You posted a damaged link to an album I can't find. -So I can't give a good opinion on the pic.

 

Ooops. Sorry should be fixed now. sorry bout that.

 

I see now. As thin as that is, it would bob like crazy in the mill. You could mill the plastic as one part, but the top wouldn't be clear like that.
You could also make the baffle with a separate bit of plastic.

Or change the design to totally take advantage of your friend.

 

I did a quick sketchup with your copper-block of 63x44mm...





high-flow, butterfly-shaped.

 

@cheapskate : i thougt that thin part wouldn't work. i like the idea of totally taking advantage of my friend but im not too sure how to proceed design wise.

@jrs77 : wow! thanks! i didn't expect someone to do that much! thanks a bunch! your design is really hot i really like it.
just a couple of questions (as im a noob to this):

There are no channels the water goes straight in and straight out will that be less efficient than a design with channels?

It looks like it is 10mm acrylic that is milled out for the top, is this enough (volume wise)?

For the groove you put around the base, i don't know if you can get Specicfic sized O-rings, would filling it with gasket sealant be as good as an O-ring?

Thanks a lot guys, i really appreciate your help!

 

McMaster sells O-rings and rubber sheet. You could fill in the gap with gasket sealant too.
If the tubing is only a 3/8" hole, then there's more space than that passing over the copper.

 

I just thought about it, how about this for better heat dissipation?



Instead of completely milling out the base, leave a couple of these ridges 3 or 4mm (width depends on what my friend's machine can do) in the base to help out spreading the heat without reducing the flow (hopefully).

*I was going to do a 3d render but my software is acting up, hope this is still as easy to understand.

 

1. yes, thats 10mm acrylic on top of the copper there in my sketch.

2. you can produce o-rings yourself in any size *hint*

3. usually it doesn't matter, if there's any fins on the block. Pumping water through the system faster, basically brings the same results, as a lowered water-flow with more area in the block.

 

Hmm, I've just got some of the red gasket sealant for sealing copper to acrylic for a passive radiator in the project I'm making. The stuff I have is called Plasket gasket sealant, made by Lawson - it contains acrylic acid, cumene hydroperoxide and methacrylate ester, and cures to a flexible seal in 1-8 hours. I tested sealing a few bit of scrap copper together 20 hours ago and the sealant was still wet in the middle when I just separated the bits.

Is this the same type of stuff you used Cheapskate? - not too keen on using it if it's going to get munched by bacteria!

 

But surely if that were true then heatblock designs from 5 years ago (which needed really good flow to perform) would get deltas just as good as pin or finned blocks. The design needs much more copper surface area imo. Not trying to be mean or anything, I just think the design is a bit flawed.

 

If you run your CPU at stock-speeds without thinking of overclocking, then a simple block as mine will cool your CPU easily.

EDIT:

Improved version with fins.

 

Yeah, true, but then why bother with watercooling? May as well stick a big aircooler on it and run it passively.

Btw, just had a look at your MNPCtech design (bent radiator) - very nice ; it's similar to what I'm doing - did you just make the design, or make the radiator as well?

 

I'm doing only the designs. Unluckily I don't have money to spend on tools to produce anything fancy.

 

I'd have your buddy just slot the crap out of the base.

 

@ cheapskate : Yeah i was thinking something along those lines too. Nothing like a friend with a CNC lol.

@Monkey Puzzle : i agree with you but another advantage of water cooling over air cooling besides low temps is...... : Silence, you don't hear much with a water cooled rig. And a big passive cooler is heavy!!! To each his own i always say.

@jrs77 : Ok thanks a lot but whats with the dual D shapes in the top, i don't really understand that bit? is it to force flow over the fins? Whats the advantage of this design?

 

The "D"-shaped parts in the acryliy-top are like the buffers in a radiator, before the water gets pressed through the fins. They basically are there to ease the pressure on the material, sealing and hoses etc.

You could also just add fins to the copper and use the acrylic-top from my first design, but fins do work best, if you force the liquid to flow faster around them.

 

I made some pictures of an old waterblock I've lying around. It died after 3 month of use, as the water-pressure was simply killing it.
You've got to notice that this one is professionally manufactured, but having a pump with 250l/hour forcing water through a block not made for high flowrates doesn't work very well.

Stock Nexxos XP light.



After three month.













You can clearly see the marks in the whole thing, where the water applied pressure to the material, more then it could handle.

That's basically the reason, why I'd opt for high flowrates.

This is the block I'd use, if I would go for watercooling again.





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Sorry for hijacking your thread