need clarification from block design folks

[Mikoto]

I just got a guy at a commercial warehousing project I manage to let me have access to his drill press. It is really BIG and cool looking I may soon have access to a mill but I'm not holding my breath, and wouldn't know what to do with CAD anyway.

I want to start playing around with block design. I don't have any really good ideas yet, I would just like to try to get a couple of functional waterblocks under my belt for the time being.

I want to know about the characteristics of heat transfer in alluminum relative to copper. In other words, is it reasonable (accurate?) to assume that a block that performs well, made of alluminum will also perform well(predictably) when constructed of copper. Can one predict, based on the conductivity of the substance how those numbers will shake out?(e.g. core temp. Al block=40C yields core temp. Cu block=35C; all other variables being equal)

Please forgive my lame attempt to clarify as I don't have to slightest bit of engineering expertise. If it is still unclear tell me so and I will try again.

The reason I ask at all is that I would rather ruin a whole mess of alluminum than a whole mess of copper Preferring instead to make several Al blocks leading to one Cu block.


thanks

 

[NeoMoses]

You are very wise, my friend. Yes, you can expect similar results from aluminum and copper. For example if you make 3 different blocks out of aluminum, the best performing Al block will also be the best performing Cu block. (All else equal).
I'll try to find some numbers or equations relating Temps with al to temps with copper.

 

[JFettig]

another copper vs al
al is tons easier to machine, tons cheaper, your temp idea is about rite

only use aluminum if you have other aluminum components(radiators, other blocks) otherwize use copper...

 

[Albigger]

another copper vs al
al is tons easier to machine, tons cheaper, your temp idea is about rite

only use aluminum if you have other aluminum components(radiators, other blocks) otherwize use copper...

i agree, but even if you do have a copper rad i would still make test blocks out of alum. and test for a week or so (long enough to get a sense of how it performs). this should be fine (as far as corrosion goes). Then when you settle on a design make it out of copper

 

[EgeWorks]

I'v had a Cu rad and an Al block running for months - no prob with corrosion, just a little additive. But my next set of blocks will be Cu just to be safer + they look prettier than Al.

 

[Albigger]

EGeWorks what addititives have you used???

 

[EgeWorks]

Car antifreeze ~5 -10% = Ethelene Glycol + Boron. I can't get water wetter where I am but it is supposed to be good too.

This stuff is only an inhibitor - theoretically there will still be corrosion/deteriation, but it is very slow.

 

[NeoMoses]

I have found that Dex-Cool (orange anti-freeze) actually inhibits corrosion better than water wetter. I came to this conclusion after putting non-anodized aluminum tops on copper blocks and running them both for 2 weeks. After 2 weeks, the Dex-Cool hoses were still clear and the hoses in the system with water wetter were completely coated with corrosion. In both setups, the system was completely closed and distilled water was used.

 

[EgeWorks]

Thanks for pointing that out - maybe it's a good thing I can't get water wetter after all.

 

[Mikoto]

Thanks for all the replies guys.

I just didn't want to pick poor designs due to variance in conductance.

I'll report back if I actually make one work

EDIT: thanks for pointing that out Masked, thats especially important to me as I have never machined anything.

 

[Since87]

I have found that Dex-Cool (orange anti-freeze) actually inhibits corrosion better than water wetter. I came to this conclusion after putting non-anodized aluminum tops on copper blocks and running them both for 2 weeks. After 2 weeks, the Dex-Cool hoses were still clear and the hoses in the system with water wetter were completely coated with corrosion. In both setups, the system was completely closed and distilled water was used.

Great info. Thanks for passing that on.

 

[JFettig]

i ran my s-type proto for like 2 weeks, it had some corosion(no inhibitors)

 

[utabintarbo]

You are very wise, my friend. Yes, you can expect similar results from aluminum and copper. For example if you make 3 different blocks out of aluminum, the best performing Al block will also be the best performing Cu block. (All else equal).
I'll try to find some numbers or equations relating Temps with al to temps with copper.

While not totally accurate theoretically, it will be close enough for your purposes.

This was the subject of much debate on another forum (I'm sure maskedgeek remembers ) with the conclusion (if any) stated above. It will do, given the tools you have access to now...

Bob