GreenMachine,
If you're handy and have some experience with milling and drill machines, then I would recommend having a base thickness of 1.75-2.25 thick whether it be aluminum or copper CDA110.
-Is this thick enough? Yes it is. 11mm stock should work fine. Just mill the surfaces smooth and totally flat.
-How deep should I drill the holes?
As deep as needed to arrive at a 1.75-2.25 thick base.
- is 8mm a good size for the holes?
Smaller is better in this realm. The Storm block is very fine. However, you may like the resistance pressure to be less. So, 1/8" or around 3.5mm would be ideal.
Another item to note, spacing between the holes should be 1.5-1.75mm apart from one another. This would require a drill station with a CNC measuring display. Even the X-Y-Z display type will help.
-What about the fittings?
3/8" or about 9.5mm is compatible with most WC'ing components. Make sure you leave enough room for the tubing over the fitting and a clamp. Don't make the fittings too short. There is 1/2" or 13mm, however, the tubing is rather difficult to run and bend. Besides, the fittings are enormous!
- should I just tap the hole, screw it in and grind off the protruding remainder?
Should work if using lock-tight or plumber's tape to remain leak free.
- what about the material of the fittings? regular steel, stainless, brass?
If you have an aluminum block, don't use brass or copper. The dissimilar metals are to close to one another and will react one-to-another. Your coolant mix would need too high of a concentration for corrosion protection then. Your goal is performance. So, Stainless or aluminum fittings would be ideal. All copper is nice too! Or Copper and Brass. And ditto on the steel that will RUST.
-on a side note, what about stainless tubing. I work with a hydraulics company and we have tons of scraps around. Is it worth the hassle?
If your WC'ing loop would be pressurized, then yes, the benefit is to go with stainless tubing. A system of 5-10psi has benefits. However, you'll need a fill/vacuum pressure system for the coolant. Somewhat complicated and not really worth the hassle. If not using pressure, but still using the SS tubing, then you'll need short 1.5" or 40mm of tubing as jumpers.
Mostly, I've worked in macro- and micron-channel blocks in the 3/8" fitting realm.
If you can use a freeware 2D CAD package, you could layout the drilled spacing to fit your block. Your outer block size should be no greater then 60x60mm in size. The basic chip surface area is about 30x30 max. The core area is a smaller foot print of around 18x18 or less. The 60x60 is ideal as dual & quad cores hit the market.
Enjoy!
Stev
(edited for grammar corrections only.
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