For all you copper vs. aluminum techies...

utabintarbo · 08-30-2002, 10:55 AM

Here's the background...

I tested 10 gazillion

w/b designs, all in aluminum, and found the absolute best/most efficient one given my current setup.

The question...

If I transferred the best/most efficient design from above into copper, could I expect the best/most efficient results vs. other copper blocks?

The premise I am trying to establish is whether aluminum is an appropriate prototyping material for w/b design.

Believe me, I'm not just trying to "stir the pot" here!

Thoughts? Comments?

Bob

bigben2k · 08-30-2002, 11:08 AM

Copper will perform better. How much depends on the flow rate used.

What do you have?

myv65 · 08-30-2002, 11:30 AM

While the performance would improve, you probably would not have the optimum copper design.

The conductivity of the base dictates how the heat will spread from the die to the fluid. Since copper's conductivity is higher, it will spread heat more in a given geometry.

utabintarbo · 08-30-2002, 03:11 PM

Quote:

Originally posted by bigben2k
Copper will perform better. How much depends on the flow rate used.

What do you have?

Stipulated. Copper will perform better for a given setup. I am wondering if aluminum would give valid results for prototyping purposes. Or would the heat propagation pattern be so different as to render any design test results invalid.

Right now, all I have is ideas!

Bob

utabintarbo · 08-30-2002, 03:18 PM

Quote:

Originally posted by myv65
While the performance would improve, you probably would not have the optimum copper design.

The conductivity of the base dictates how the heat will spread from the die to the fluid. Since copper's conductivity is higher, it will spread heat more in a given geometry.

I would think that the conductivity of the block medium would be less of a factor than the "heat-holding capacity" (insert appropriate technical term please) of the medium. This would alter the propagation pattern from one medium to another, no?

Bob

maskedgeek · 08-30-2002, 03:22 PM

well id say go for it and mill a copper one(you have a mill rite or acess to make these?) if its a tiny desktop cnc do like .03inch passes.

i bet your aluminum one will perform very close to the copper one... VERY close... try it and see what happens

gone_fishin · 08-30-2002, 03:45 PM

Most definately the comparison would not be a good one. The spread of heat in copper is so much greater that what is needed for a good spread in aluminum is drastically different than in copper. Just take the base thickness as an example, then there is the dimensions of any geometry above the base thickness. The heat spread characteristics of the two would make any comparison be like apples to oranges in an equally dimensioned design comparison. Remember the die sizes of the cpus are small to begin with so heat spread is extremely important. Prototyping in aluminum to get a model can be of use but then you could use plastic also to make a model cheap and easy.

bigben2k · 08-30-2002, 03:50 PM

Quote:

Originally posted by utabintarbo
I would think that the conductivity of the block medium would be less of a factor than the "heat-holding capacity" (insert appropriate technical term please) of the medium. This would alter the propagation pattern from one medium to another, no?

Bob

Actually, the conductivity is a large factor, I think that's the point that myv65 is trying to get across.

In other words, if your Alu baseplate is too thin (probably under 10mm), then the difference in a similar copper WB would be affected.

Check it out (goto page 2).

utabintarbo · 08-30-2002, 04:29 PM

Quote:

Originally posted by gone_fishin
Most definately the comparison would not be a good one. The spread of heat in copper is so much greater that what is needed for a good spread in aluminum is drastically different than in copper. Just take the base thickness as an example, then there is the dimensions of any geometry above the base thickness. The heat spread characteristics of the two would make any comparison be like apples to oranges in an equally dimensioned design comparison. Remember the die sizes of the cpus are small to begin with so heat spread is extremely important. Prototyping in aluminum to get a model can be of use but then you could use plastic also to make a model cheap and easy.

I don't think I would want to actually test a plastic block... make for heap big mess!

So what I am gathering from your post, is that the heat propagation thru the al is so different from cu that it would render any comparison invalid. Correct?

What if we reduced the amount of al the heat had to go thru to get to the water, ie. thinning the base plate. Would that help? Can we come up with a "ratio" of base plate thickness which would be valid?

Like I said, I'm not trying to cause controversy. Just trying to get my facts straight.

Bob

gone_fishin · 08-30-2002, 04:58 PM

If you changed anything then you wouln't have a model of the block you plan to make in copper, I don't see the point.
I did not intend the plastic example to be attached but to use as a model to copy in copper.

Jessfm · 08-30-2002, 07:01 PM

.
Totally different R&D
Everything that's needed to pointed out has been, but Copper is far superior to Alum.
Both have their good and bad sides though, this is why on paper Silver looks so good.
You think WB manufacturers R&D is Alum - I for one don't and if any of them did , you should be able to see the crappy thermal transfer properties a mile off

myv65 · 08-30-2002, 08:36 PM

Quote:

Originally posted by utabintarbo
I would think that the conductivity of the block medium would be less of a factor than the "heat-holding capacity" (insert appropriate technical term please) of the medium. This would alter the propagation pattern from one medium to another, no?

Bob

This is a common misconception and a large part of the "aluminum better at getting rid of heat" myth. For the most part heat transfer from our CPUs is a steady-state phenomenon. This means that once everything has been running a while, the temperature at any given point within the system no longer changes. Once you reach this point, specific heat has absolutely zero bearing on heat transfer.

All specific heat does is determine how long it takes to heat up a material (or cool down) when a heat source is added (or removed).

Some folks think that since the water flows through the block you couldn't possibly have steady-state. It's all a matter of definition. Yes, the water undergoes a warming and cooling cycle as it circulates through the loop. At any given position within the system, however, the water there will be a steady temperature after the initial warm-up period ends. To an engineer, this is still steady-state.

My take on your posts is that you would like to find the "optimum" aluminum shape for a block and then begin making it in copper. I guarantee you will not have the ideal copper shape if you follow this method.

Honestly, however, we're really splitting hairs when we start talking about "optimum". Any block will have different results depending on the amount of heat from the processor, the size/shape of the die, and the flow rate of the fluid. This means there is no single optimum that applies universally to all situations. We're also talking about small differences between the "best" blocks that take different philosophies to cooling (direct impingement, spirals, multiple cross channels, etc.).

What would be kinda neat would be to see a manufacturer employ investment casting to produce blocks. You'd have a near-final geometry that would require nothing more than mounting a cap and final grinding of the base. It would also have a low cost per part (but pretty high tooling cost for the die). I guess there just isn't enough demand to justify that initial investment.

Heavy_Equipment · 08-30-2002, 08:40 PM

Quote:

i bet your aluminum one will perform very close to the copper one... VERY close... try it and see what happens

...don't mind him, he's ignorant to fact, argues with reason and experience, and he talks out of his ass.

I'm not flaming him, I'm warning you Bob.

Jessfm · 08-30-2002, 08:51 PM

myv65

Cast would be overall better value for end users too.
BUT as you rightly point out its demand, also you would have to have a very long lifespan on the base design, TBH consumers are funny , they seem to want different things as the wind changes. First it was perfromance, then looks - now its both, and all with no extra cost.
AT least with CNC we can change our designs slightly for very little cost so long as the Bed don't need to be changed.

utabintarbo · 08-30-2002, 10:31 PM

Quote:

Originally posted by myv65

My take on your posts is that you would like to find the "optimum" aluminum shape for a block and then begin making it in copper. I guarantee you will not have the ideal copper shape if you follow this method.

Honestly, however, we're really splitting hairs when we start talking about "optimum". Any block will have different results depending on the amount of heat from the processor, the size/shape of the die, and the flow rate of the fluid. This means there is no single optimum that applies universally to all situations. We're also talking about small differences between the "best" blocks that take different philosophies to cooling (direct impingement, spirals, multiple cross channels, etc.).

Yeah, this is what I am trying to get at. What I see from your (and other's) posts is that aluminum is not an "ideal" prototyping material for (ultimately) copper blocks, but it may get one into the ballpark. Given the relative ease of manufacture of aluminum blocks, my premise as stated above would seem to be (partially) validated, no?

Bob

utabintarbo · 08-30-2002, 10:32 PM

Quote:

Originally posted by Heavy_Equipment
...don't mind him, he's ignorant to fact, argues with reason and experience, and he talks out of his ass.

I'm not flaming him, I'm warning you Bob.

Thank you for your concern, however I wish him good luck in his endeavours also.

Bob

maskedgeek · 08-31-2002, 12:57 AM

Quote:

Originally posted by Heavy_Equipment
...don't mind him, he's ignorant to fact, argues with reason and experience, and he talks out of his ass.

I'm not flaming him, I'm warning you Bob.

um.. thanx for the compliment....

im talking out of what iv seen, iv seen it many times! if you wanna think that go ahead

maskedgeek · 08-31-2002, 01:14 AM

Quote:

Originally posted by Heavy_Equipment
...don't mind him, he's ignorant to fact, argues with reason and experience, and he talks out of his ass.

I'm not flaming him, I'm warning you Bob.

weres your proof besides the numbers and theory, pleze show me.... iv had real proof, jaydee has had real proof, webmedic has real proof... hmm ill see how many more i can think of..

Fixittt · 08-31-2002, 01:35 AM

I have tried investment casting. Its a no go for me. One, I could not find someone local that pours pure or close to pure copper. It was always a huge ratio alloy. Second, after the casting was made, and I did my finish up machining to the base plate. at 5 mm thick I gor water leakes. It would seem that with this thin of a base plate the pours were connected and allowed water to seep out. Just my experiance. So I scrapped the idea.

maskedgeek · 08-31-2002, 01:42 AM

Quote:

Originally posted by Fixittt
I have tried investment casting. Its a no go for me. One, I could not find someone local that pours pure or close to pure copper. It was always a huge ratio alloy. Second, after the casting was made, and I did my finish up machining to the base plate. at 5 mm thick I gor water leakes. It would seem that with this thin of a base plate the pours were connected and allowed water to seep out. Just my experiance. So I scrapped the idea.

are you in the rite thread? well if you are, your stuck here now

Fixittt · 08-31-2002, 07:34 AM

was late last night, thought I read somewhere at the front about someone wanting to see us use investment casting....... like I said it was late.

MadDogMe · 08-31-2002, 10:07 AM

Quote:

What would be kinda neat would be to see a manufacturer employ investment casting to produce blocks. You'd have a near-final geometry that would require nothing more than mounting a cap and final grinding of the base. It would also have a low cost per part (but pretty high tooling cost for the die). I guess there just isn't enough demand to justify that initial investment.

You were'nt dreaming

...

Quote:

...don't mind him, he's ignorant to fact, argues with reason and experience, and he talks out of his ass. I'm not flaming him, I'm warning you Bob.

There's always one

. Just how would you define Flaming?. like this?:

*******************************************

Personaly I'd take no notice of Heavygear if I were you. He believes using a bong to cool a CPU will give you Legionaires disease!! ROFLMFAO!!.

Just warning you Bob

...

Quote:

Heavygear:
I used a bong for two weeks, and IMO, it wasn't worth the hassle.
...or the health risk.

Legionaires Disease

*******************************************

...if not ~don't take it personaly

...

:shrug:

Jessfm · 08-31-2002, 10:28 AM

MadDOg,

Whilst I don't want to get into a defending/argument myself, there is a risk of Legionnaires disease (even if its small) if a bong is used - not to mention the problems with vapour from other additives.

But just exhaust outside to get around the health risk directly

MadDogMe · 08-31-2002, 10:38 AM

No prob!, but...

...I'm scared to go into the bathroom now!

...

Have there been any recorded cases?. if not IMO it's not a possibility, as such!. if you look at it like that there's always the risk of being flattened by a falling satilite every time you cross the road!. it could happen! does that make crosing the road a 'satilite puree' risk?. they should put signs up!

Is the density of cast copper alot less than drawn/extruded copper?. as cast ali' is compered to 'normal' ali'?. if so it would throw the properties out would'nt it?. is'nt coppers density part of it's (good[for us!]) thermal property?.

Do you think it'd all be that porus?, or was that a 'bad batch'?...

Heavy_Equipment · 08-31-2002, 11:33 AM

As for the comments to Maskedgeek, yes, I did flame him.
For the record: I'm sorry.

I usually ignore crap like that, (the other thread on this subject...the one that pissed me off) but when he came to utabintarbo's thread, and started the same BS again, it pushed my buttons.

Now, a word to the wise, pneumonia is a strong possibility when using a bong cooler, especially to past pneumonia sufferers, and people with other breathing conditions.
Whether full blown Legionaire's occurs or not, I just wanted to bring a potential health risk to light.

Do what you want, you will anyway.

08-30-2002, 10:55 AM	#1
utabintarbo Cooling Savant Join Date: Jul 2002 Location: Sterling Hts., MI Posts: 496	For all you copper vs. aluminum techies... Here's the background... I tested 10 gazillion w/b designs, all in aluminum, and found the absolute best/most efficient one given my current setup. The question... If I transferred the best/most efficient design from above into copper, could I expect the best/most efficient results vs. other copper blocks? The premise I am trying to establish is whether aluminum is an appropriate prototyping material for w/b design. Believe me, I'm not just trying to "stir the pot" here! Thoughts? Comments? Bob __________________ Sarcasm is yet another of the free services we offer!

08-30-2002, 11:08 AM	#2
bigben2k Responsible for 2% of all the posts here. Join Date: May 2002 Location: Texas, U.S.A. Posts: 8,302	Copper will perform better. How much depends on the flow rate used. What do you have? __________________ WBTA (Water Block Testing Alliance) Nordic Hardware WC 101

08-31-2002, 01:35 AM	#19
Fixittt CNC Beyatch Join Date: Aug 2001 Location: Tulsa Spell it backwards Posts: 721	I have tried investment casting. Its a no go for me. One, I could not find someone local that pours pure or close to pure copper. It was always a huge ratio alloy. Second, after the casting was made, and I did my finish up machining to the base plate. at 5 mm thick I gor water leakes. It would seem that with this thin of a base plate the pours were connected and allowed water to seep out. Just my experiance. So I scrapped the idea. __________________ Creator of the Spir@l Block Longest post ever http://forums.procooling.com/vbb/showthread.php?s=&postid=43808#post43808

08-31-2002, 07:34 AM	#21
Fixittt CNC Beyatch Join Date: Aug 2001 Location: Tulsa Spell it backwards Posts: 721	was late last night, thought I read somewhere at the front about someone wanting to see us use investment casting....... like I said it was late. __________________ Creator of the Spir@l Block Longest post ever http://forums.procooling.com/vbb/showthread.php?s=&postid=43808#post43808

08-31-2002, 10:38 AM	#24
MadDogMe Thermophile Join Date: Aug 2002 Location: Just shut up ;) ... Posts: 1,068	No prob!, but... ...I'm scared to go into the bathroom now! ... Have there been any recorded cases?. if not IMO it's not a possibility, as such!. if you look at it like that there's always the risk of being flattened by a falling satilite every time you cross the road!. it could happen! does that make crosing the road a 'satilite puree' risk?. they should put signs up! Is the density of cast copper alot less than drawn/extruded copper?. as cast ali' is compered to 'normal' ali'?. if so it would throw the properties out would'nt it?. is'nt coppers density part of it's (good[for us!]) thermal property?. Do you think it'd all be that porus?, or was that a 'bad batch'?... Last edited by MadDogMe; 08-31-2002 at 10:44 AM.

08-30-2002, 11:30 AM	#3
myv65 Cooling Savant Join Date: May 2002 Location: home Posts: 365	While the performance would improve, you probably would not have the optimum copper design. The conductivity of the base dictates how the heat will spread from the die to the fluid. Since copper's conductivity is higher, it will spread heat more in a given geometry.

08-30-2002, 03:22 PM	#6
maskedgeek Registered User Join Date: May 2002 Location: poop Posts: 145	well id say go for it and mill a copper one(you have a mill rite or acess to make these?) if its a tiny desktop cnc do like .03inch passes. i bet your aluminum one will perform very close to the copper one... VERY close... try it and see what happens

08-30-2002, 03:45 PM	#7
gone_fishin Cooling Savant Join Date: May 2002 Location: Da UP Posts: 517	Most definately the comparison would not be a good one. The spread of heat in copper is so much greater that what is needed for a good spread in aluminum is drastically different than in copper. Just take the base thickness as an example, then there is the dimensions of any geometry above the base thickness. The heat spread characteristics of the two would make any comparison be like apples to oranges in an equally dimensioned design comparison. Remember the die sizes of the cpus are small to begin with so heat spread is extremely important. Prototyping in aluminum to get a model can be of use but then you could use plastic also to make a model cheap and easy.

08-30-2002, 04:58 PM	#10
gone_fishin Cooling Savant Join Date: May 2002 Location: Da UP Posts: 517	If you changed anything then you wouln't have a model of the block you plan to make in copper, I don't see the point. I did not intend the plastic example to be attached but to use as a model to copy in copper.

08-30-2002, 07:01 PM	#11
Jessfm Cooling Savant Join Date: Apr 2002 Posts: 110	. Totally different R&D Everything that's needed to pointed out has been, but Copper is far superior to Alum. Both have their good and bad sides though, this is why on paper Silver looks so good. You think WB manufacturers R&D is Alum - I for one don't and if any of them did , you should be able to see the crappy thermal transfer properties a mile off

08-30-2002, 08:51 PM	#14
Jessfm Cooling Savant Join Date: Apr 2002 Posts: 110	myv65 Cast would be overall better value for end users too. BUT as you rightly point out its demand, also you would have to have a very long lifespan on the base design, TBH consumers are funny , they seem to want different things as the wind changes. First it was perfromance, then looks - now its both, and all with no extra cost. AT least with CNC we can change our designs slightly for very little cost so long as the Bed don't need to be changed.

08-31-2002, 10:28 AM	#23
Jessfm Cooling Savant Join Date: Apr 2002 Posts: 110	MadDOg, Whilst I don't want to get into a defending/argument myself, there is a risk of Legionnaires disease (even if its small) if a bong is used - not to mention the problems with vapour from other additives. But just exhaust outside to get around the health risk directly

08-31-2002, 11:33 AM	#25
Heavy_Equipment Cooling Savant Join Date: Mar 2002 Location: Newmarket, Ontario, Canada Posts: 282	As for the comments to Maskedgeek, yes, I did flame him. For the record: I'm sorry. I usually ignore crap like that, (the other thread on this subject...the one that pissed me off) but when he came to utabintarbo's thread, and started the same BS again, it pushed my buttons. Now, a word to the wise, pneumonia is a strong possibility when using a bong cooler, especially to past pneumonia sufferers, and people with other breathing conditions. Whether full blown Legionaire's occurs or not, I just wanted to bring a potential health risk to light. Do what you want, you will anyway.

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