[leejsmith]

Originally posted by deepblue
@jd

first up.. i don't get along with inch and that stuff quite so well, so i'll use metric values instead

hm roundbottom cups will surely be much more efficient than any flatbottom cups. you've shown a pretty good example with those little 3ds anims. the hemisphere will guide the water easily along the walls out of the cup whereas the flat bottom will cause massive turbulences that will hinder the water from doing much of anything (good). all in all this might slow down the exiting water quite some...

if the cup base is round the water will just flow out with no impingement happening. This is good for flow rate but not for heat transfer. The cups need to be flat.

another point about the pipes. get them to dip as much into the cup as you dare. the ideal distance between cup-button and pipe-bottom should be somewhere around 1mm - so if you're cup is 4mm deep, make sure the pipe reaches about ~3mm into the cup.

i have 3mm copper and have tried tubes 0.8mmID/1.5mmOD. first i start with them 2.0mm inside the cups and then 1.5 and 0.5. the best results was at 0.5mm. If the tubes are too close to the cup base the jet will not form correctly. For 0.8mm ID the tubes should be at least 4mm above the cup base.

the next thing is the strength (width?) of the remaining baseplate below a cup. the thinner, the better - but that might make room for mess-up since if to thin, the baseplate might be deformed when trying to mount it. so i'd advise you to stick with 1mm.
- what i'm working on so far is - if that can be machined by friends of mine - about 0.6-0.8 mm below the centermost cups and up to 1mm of those around that (with pipes that follow suit).
- this of course can only be done with a cnc, since you can't drill that exact by hand...

I agree the amount of copper above the cpu core should be as thin as possible. Also the amount of copper between each cup should be the same.

overall baseplate strength is ~5mm

and for pipes.. well try brass pipes.. there's some that have an ID of 0.6 mm and OD of 1.2mm - others are 0.8/1.5mm (ID/OD). those should be perfect. and to fix them you could either try making the plate for the pipes from copper aswell and drill tight holes into it, trying to pull the shrink/fit thing, or you can use your polycarb and superglue the pipes into.. should work aswell

using superglue with the brass tubes in polycarb is ok as long as the superglue is ok for use in water Some superglue is not.

that should do it..
oh.. cup diameter.. hm let's see... assuming you use the 0.8/1.5 brass pipes, you should make the cups ~2.5mm wide..

the cups should be 3*the tube ID too little and the water will be sucked out. Too much and the jets wont be able to cool anough of the cup area.