Co2, hmm that might be useable. Though I think ive decided to scrap the casting idea now.. lost wax aka investment casting is the way my dad suggested a few days ago, which to do properly without air in the copper seemed expensive, so I thought about another way... My dad doesnt really like the idea of me plaing with 1500c flames in the garden though! and the gpu block made him think theres not much point in casting a block, and to be honest, id have to agree...
So instead hes been playing with about 5x more silver than I used in the gpu block, at work, and I have yet to see what he has created!
Id definatly recommend you try making your own blocks, rather than buy a DD maze4 like most ppl
Ive found that copper piping is a very cheap way to do it but as normal copper is cheap you might want to buy a big bit instead.. but it will take more effort to mill out!
another reson i wanted to use copper piping for my blocksis the tube is 15mm ID and 17mm ID for the fittings/bends, so slightly less low restriction compared to the normal 8-12mmID usually used.
My gpu block should hopefully be finnished and soldered up tomorrow. all thats left to do first is drill the second hole in the lid. I didnt have the right size drill bit (17 or 18mm) so i used the biggest I could find, 8.5mm! Then I used a round file to get it right, then I went to far.. so now it looks bad. Im hoping the solder will fill all the gaps, or Ill have to make another lid
Edit - tryed soldering the gpu block together. didnt manage to get it leak free though. its too dificult soldering the base to the lid at the same time as pipe to an elbow, and elow to the lid, while the holes in the lid arnt nearly perfect.
thinking about an easyer way...