What sealant for homebrew WB?

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Pherret

Limp Gawd
Joined
Aug 18, 2002
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Im going to build a waterblock that will use 3 sandwiched plates. 1/4" copper plate, 1/2" aluminum center channel plate and a top 1/4" aluminum top plate.

It will end up held together with probably 8 screws but I think more would be needed to make sure it doesn't leak.

Silicone type stuff I hear tends to get "Enflamed" as it absorbs water and thus becomes a cooling/flow problem. Most epoxies from what Ive seen don't handle water well either.

Is there any good sealant out there that I could maybe goop on before everything is bolted together?
 
I made a waterblock from an old heatsink once. I just used plexi glass and JB weld. It held up very well for about 3months, it kept my CPU 2 degrees above ambient. After 3 months it developed a major leak in the night. It burned out a PCI slot, and my video card.
 
Originally posted by Pherret
Im going to build a waterblock that will use 3 sandwiched plates. 1/4" copper plate, 1/2" aluminum center channel plate and a top 1/4" aluminum top plate.
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This is a really bad idea, make it all out of one metal- preferably copper. Having those two metals in contact will result in corrosion of the aluminum pieces in no time.
 
switch to all copper plates and silver solder the edges shut.
other than allowing for the solder sealing route, you will avoid corrosion problems with an all copper block...

all you need is the fairly cheap propane based torch kit from lowe's, home depot or walmart (usually called a 'plumber's kit) and maybe a 2 or 3 c-clamps.

cut the channels you want into the block, clamp the plates in place with the c-clamps, then just fire up the torch and heat the plates until the solder will flow along the edges -- go all the way around the block, check to make sure there is a coating of the solder on all 4 sides and then let it cool. after it cools, test for leaks. if all is good, lap the base until it is nice and flat and the block is ready for use.

using copper plates makes this fairly easy. :)
 
Originally posted by weapon--
switch to all copper plates and silver solder the edges shut.
other than allowing for the solder sealing route, you will avoid corrosion problems with an all copper block...

all you need is the fairly cheap propane based torch kit from lowe's, home depot or walmart (usually called a 'plumber's kit) and maybe a 2 or 3 c-clamps.

cut the channels you want into the block, clamp the plates in place with the c-clamps, then just fire up the torch and heat the plates until the solder will flow along the edges -- go all the way around the block, check to make sure there is a coating of the solder on all 4 sides and then let it cool. after it cools, test for leaks. if all is good, lap the base until it is nice and flat and the block is ready for use.

using copper plates makes this fairly easy. :)
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If you're Really paranoid, you can coat your joint with fish tank sealant after the solder cools.
 
on the blocks that I have made, I use basically the same torch and tactics that I use for making phase change evaporators.

15% silver brazing rods and quite a bit more heat than is required for standard soldering -- i.e. 535 degrees F for Harris' Stay-Brite #8 vs. 1480 degrees F for Stay-Silv 15

on the bright side, after the fittings and the sides are brazed like this, it is good for pressures that are associated with phase change -- which are one helluva lot higher than the pressures associated with H2O cooling. I've tested some of the blocks with a 5 cfm vacuum pump and they will hold 29" of vacuum indefinitely...that is about as sealed as you can get. :D
 
a cheap sealant would be a rubber gaskit (sp?).

Or the soldering theng, but the gaskit is cheap, and easy to do (not to mention quick).
 
Originally posted by triple_s
a cheap sealant would be a rubber gaskit (sp?).

Or the soldering theng, but the gaskit is cheap, and easy to do (not to mention quick).
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Soldering is cheap, quick, and not hard at all. I bet it would be more of a pain to cut a gasket, considering all the chambers, inlets, and screw holes you have to deal with.
 
many companies do alu and Cu in combination in waterblocks. I realize the inherant problems in mixing the two with the galvonic corrosion and all.

Are the black ice rads aluminum? There are areas where the the paint is chipped on mine and the water channels seem to be alu but the interconnecting fins seem to be Copper. In that case I will already be putting aluminum into the system.

Now that I think about it the pump tank I ordered is Aluminum as well.

Then the more aluminum in the system the slower each piece will be eaten away at right ;)
 
....not really, no. Copper fins soldered to an aluminum base arent the same as water passing through both aluminum and copper. Combining the two via conitinuous liquid really does lead to corrosion.
 
Originally posted by NoEcho
....not really, no. Copper fins soldered to an aluminum base arent the same as water passing through both aluminum and copper. Combining the two via conitinuous liquid really does lead to corrosion.
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Especially in close contact. The corrosion rate considering contacting Al and Cu plates will be exponentially greater than the rate considering pieces separated by some distance (like a Cu block and an Al reservoir.)
 
so like I said before, what about the companies that mix the two in WBs such as Innovatek and Swiftech. Does the fact that the aluminum is anodized realy make a difference?
 
Originally posted by Pherret
so like I said before, what about the companies that mix the two in WBs such as Innovatek and Swiftech. Does the fact that the aluminum is anodized realy make a difference?
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Yes, the anodization makes all the difference. It forms a protective coating over the aluminum. However, the aluminum can still corrode through pinholes, scratches, or tiny imperfections in the anodization.
 
... which is why I hang on to my Maze3. I like having a chunky all copper water block. No plastic/aluminum here.
 
Ok then is only a 1/4" deep center plate advisable? 1/4" is all I have in copper. There must be about 1/2" of thread on my barbs.

Edit: I would need to cut some off of the barb.
 
Originally posted by Pherret
Ok then is only a 1/4" deep center plate advisable? 1/4" is all I have in copper. There must be about 1/2" of thread on my barbs.

Edit: I would need to cut some off of the barb.
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1/4" is deep enough with no probs.
I have some copper blocks that are made with nothing but two .1875 thick pieces of C110 bar.

If you have to, cut off some of the lower threads on the fittings and silver solder those suckers in place. works for me...
blueblockrszd.jpg


as for the res, you can make those out of copper as well (pic of a greatly unfinished 100% copper, fully brazed weapo-res :D -- it will have 1/2" barbs and some paint work soon)
weapresrszd.jpg


no corrosion no corrosion no corrosion. :p
 
Nice looking stuff! The barbs Ive got are DangerDen, which, I think are nickle plated or something to make them nice and shiny. Would soldering to them destroy the plating? Maybe I could just use some teflon tape instead?

Edit: Im starting to think about other simple design possibilities. Ive got some decent quality wood/metal hole saws. One of which I use for making holes for 40mm fans. I wonder If I could just saw a hole in the center plate, and drill some dimples in the base plate, for surface area, like they did in older swiftec designs.

Now Im trying to think of how large that hole saw is in comparison to the copper bar I have... I think it is 2in wide flat bar... 4cm/2.54(cm/in)=1.57in so it might be a 1.5in hole saw which would hopefully work.
 
if there is a plating on the fittings, odds are that you should rule out the soldering on the fittings. just used teflon tape or maybe pipe thread sealant.

the copper bar that I start with is usually 2" x 3" x .1875" or 2" x 3" x .25"

with a 3 plate block, I use one .1875" or a .25" for the baseplate, one .25" for the top plate (extra room for the threads) and one .125" plate for the middle plate.

example of a 3 plate block:
Dscn0805.jpg


same block during brazing:
block2torsch.jpg

:D
 
I see you use 2 torches when doing that. Are they both needed to get it to temp? What do you use to hold it that doesn't sink away the heat?

Then there is mounting. I will want to conserve the copper in case of future ideas so keeping the block itself small will be usefull(meaning not spanning to the mounting holes). Maybe I could screw the block to some of my aluminum which would reach the holes. Then bolt them down with some springs. What hardware do you guys use for this? Springs of the correct compression may be tricky to find. I thought I saw a screw mounting kit at d-tek or something. Ahh here it is.
 
i was using a propane and a mapp torch just to get it hot more quickly -- that is for brazing with 15% silver rods.
a single propane torch will get it hot enough for brazing if you use a decent torch (A berzomatic TS4000 will work).
if you use Harris' StayBrite 8, you dont have to get the copper anywhere close to that hot as 535 F is all it takes.

I use either a fire brick, a ceramic tile or a fire insulating pad I got from the local HVAC store when I braze blocks.

side note: don't lap the block until after the brazing or soldering -- it will get a very slight warp when you braze it and you will just have to lap it again.

also, after any torch work, the block will pretty much look like h311 -- a little cleanup in the sink with an SOS pad will get rid of most of the mess. you can fill the block up with Eagle Mag Wheel Cleaner (the etching type) over nite to clean the garbage out of the inside of the block -- just rinse it out with a lot of warm water the next day.

the aluminum adapter plate idea would work as far as using it with a smaller copper block -- you will want it to apply pressure across the middle of the block though. A semi-X shaped aluminum plate with the middle cut out for clearance of the block fittings seems to work alright.

the dtek mounting kit or the one from danger den will work for 4 hole mounting.
 
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