Brass as a water block? Possibly a very cheap block

[orev]

I was wandering around the plumbing section in Home Depot the other day and came across an interesting part. It was a brass 90 degree elbow with a flat bottom. It's basically a cube of metal with 2 holes drilled at 90 degrees to each other, and a nice flat surface on one side that would line up very nicely with a CPU core.

It got me thinking about the nano block, and it seemed like it would be very simple to buy 3 parts, no more than $8 total, and you'd have a nano block.

However, it brings up some questions:
1. Has anyone used brass as a water block? What type of heat transfer can I expect?

2. The tough one, where to get a hold down for this sort of thing? The input fitting would come vertically out from right above the core, so a normal hold down won't allow pressure to be put in the center of the core.

Thanks.

[mx-6*]

It would suck.

I saw those things in Home Depot and thought the same thing, but I couldn't find any copper ones. Too bad, brass doesn't absorb and transfer very well.

[Cyco-Dude]

you could just make a hold down of of an acrylic sheet and get a Maze2 hold hardware to bolt it to the 4 holes around the socket (for AMD cpus anyway). improvise!

[decodeddiesel]

Well sure you could build it, but Brass is a horrible conductor of heat. We are talking almost as bad as steel here.

[jaydee]

Originally posted by decodeddiesel
Brass is a horrible conductor of heat. We are talking almost as bad as steel here.

That and it's rigitity is why they use it for bushings.

[orev]

Damn, and I was hoping to get something nice and small. If brass won't work well, forget it.

Anyone know where to get a nano block type of thing?

[Brad]

what about Al? have you asked home depot about Cu or Al versions

[mkosem]

orev, make one. get a drill and a chunk of copper, drill it in one direction, then drill it in the other. then, if you don't have taps, have someone tap the holes for you so you can screw in some fittings. or you could pull a chip and JBWeld/goop some fittings on there.

--MAtt

[UnaClocker]

I should probably chime in here.. I've actually used a brass waterblock before. It did work, and I believe the thermal conductivity of brass is either just above, or just below aluminum. So it's not the end of the world if you use brass. It sure polishes up nice! If your doing the block with CNC equipment, you could use brass for the top of the block, cut all your passages into it, and solder on a 1/4" copper bottom plate to transfer heat properly.
Oh, and my brass block.. It was my first Socket based waterblock, my father made it for me at his machine shop. Why he picked brass when I asked for copper, I'll never know. I used it on a Duron 650 on an FIC AZ11 board. I never really got a temp reading from it, and that board, even after extensive moddding) never overclocked past 800.. Oh, and the block was drilled passage.. Good old style that works better than most people give it credit for.

[Mr Evil]

Brass waterblocks do work. Here's one I made earlier:



Depending on the proportions of metals used in the alloy, the thermal conductivity can vary widely from well below aluminium to almost as good as copper.

[Heavy_Equipment]

I didn't want to admit this.

I used the same brass 90 for a few weeks, before this Z3 came in way back. It had my Duron 750 running about 10C hotter than the Z3 on the exact same cooling system. Point is, it worked...just not great.

I made the hold down from a length of 3x3 alum. angle also from Home Depot. I cut it just wider then the socket, and drilled 3 holes. The center hole was a size larger than the fitting, so it sat on the brass, with the fitting poking through. The hold downs were just 3" bolts with nuts. I shaved enough of the head with a dremel, that I could hook the centre zif lug, without touching the mobo. The bolts poked up through the angle on either side of the fitting, and I hand tightened the nuts. I don't remember exact temps...but it was real close to 50C on a stock 750.

[Brad]

brass is 89cmk I think, while Al is 200 something, and copper is 400, I don't think copper is all that close to Al

[#Rotor]

http://www.cs.ubc.ca/cgi-bin/nph-per...periodic-table


very handy for a quick-reff.

[Brad]

brass isn't an element, so that tables fairly useless for what we need right now anyway

[Heavy_Equipment]

What is brass anyway...nickel/copper alloy?

*EDIT*
Ok, I was lazy. I found it though.

Dictionary.com-
Brass:
"A yellowish alloy of copper and zinc, sometimes including small amounts of other metals, but usually 67 percent copper and 33 percent zinc"

Using the periodic table...
Cu has a Thermal Conductivity of.94, Zinc is .27
Cu has a Specific Heat Capacity of .092 Zinc is .0915
Al is .5, and .215 respectively.
So loosely rounded off, assuming that brass's thermal properties would be equal to the 67/33% copper/zinc, that would make it roughly equal, if not better than Al in the conductivity, and virtually equal to copper in capacity. Based on that, I can see MR. Evil's side. Even though a 90 degree elbow is a crappy waterblock,(go figure???) brass could be a good middle-of-the-road performer.

Not to be a smartass, I was just bored.

[Butcher]

Alloys of materials do not maintain the same thermal conductivity as merely mixing the materials.
Here's a few numbers:
Yellow Brass (65/35) - 116W/m-K
Red Brass (85/15) - 159W/m-K
Al 1050-O (99.6/) - 234W/m-K
Al 6063-O (98.9/) - 218W/m-K
Al 6063-T5 (98.9/) - 209W/m-K
Cu C11000 (99.9/) - 388W/m-K

Al smokes brass, Cu smokes Al.
Now most Al HSFs are made of one of the various tempers of Al 6063, T5 is certainly one used, I doubt O is used (O is annealed Al). As you can see even tempering reduces the conductivity.
Cu blocks / HSFs are made from standard C11000 copper mostly, nice high conductivity.
Brass is well below both, plumbing items in home depot are most likely yellow brass, barely above half as good as even Al. Better to get yourself a cheap chunk of copper and drill it.

[UnaClocker]

Ok Butch, since you seem to know where to look these things up, look up 6061 AL for me.. Thanks..