This was a new approach for making a waterblock. In stead of the standard crossdrilled, I decided to solder on a brassbox on top of a copper baseplase. Inside the waterblock there are lamells of thin copper which serve as turbulators and they also increase the surface area inside the block.
Fig. 7 The waterblock before lapping.
This is what it looks like in the beginning. The base needs to be lapped and the rest of the block needs to be painted. I chose high gloss Tamyia black modelpaint for this job. You want to apply the paint in layers, or you'll have problems with the paint dripping off and this doesn't look good.
Fig. 8 The waterblock after lapping.
Fig. 9 The waterblock painted.
Testing the cooler
In every project involving watercooling, it is very important to run it outside your comuter to check for leaks etc. Make no mistake; it is not fun to discover that there's about 10 litres of water gushing inside your computer.
Fig. 10 The watercooler being tested for leaks.
In the picture above you can see the test bench. The radiator is inside the computer case, but exctept for that, everything you need is in the pic; the Eheim 1048 pump, a 250W variable 12-24V powersupply for the peltiers, waterblock with two 90W peltiers, hoses and a red bottle that I've used as a reservoir.
Notice the two following pictures. These are before and after powering up the watercooler, and, as you see on the last picture, there are quite a bit of ice forming on the coldplate. The temerature measured on the coldplate with no load was aproximately -25C.
Fig. 11 Before firing up the cooler.
Fig. 12 After firing up the cooler.
Whenever you have a cooling system that go below your ambient temperatures, or actually the dewpoint in the room, there will be some condence. The dewpoint in a room with a temperature of 20C may vary from 13C to 17C depending on the relative humidity in the surrounding air. Needless to say, when operating at sub-zero temperatures, you will have serious problems if you don't insulate properly.