[Khledar]

Hello,
I'm in the process of attempting to make some sort of water cooling device from a slew of misc. parts for a currently non existent computer, soudns liek fun eh? Only problem is I have next to no clue what I'm doing.

What I have:
Water Pump (I figured this would be necessary)
Heater Core (Ripped out of a camper van that is in a state of disrepair :P )
Misc. Tubing
Lucite(Clear Acrylic Sheet- Which I plan to build some sort of resevoir out of)
Copper (I figure this is required also):
3ft long, 4in wide and 1/2in thick (thickest stuff I could find locally in quantities less than like 100lbs or something)
A thinner sheet of copper a bit longer and wider than the previous piece, but also a lot thinner, maybe about 1/16" (The metric system I know tells me 1-1.5 mm)

I kinda started (tried) to make a HD cooling device, by taking a 6in long by 4 in wide piece of the plate copper and measuring out a pattern and ummm kinda drilling into it. The plan was to cut out a pattern all the way through and then affix two peices of the thinner copper on either side. The big problem comes in two flavours. Flavour number one: I don't have a clue how to solder two pieces of metal together, let alone three!(Please give me some tips). Flavour number two: the water path will end up being oval(rectangular) as it is 1/4" thick(copper plate) and is cut 1/2" wide path, how would I go about making a round pipe fitting flow with maximum volume:sec ratio?

I'm really a newbie in need of ideas/experience, any suggestions are welcome. If you have any ideas as to how to make a CPU waterblock from the supplies I have, I would be quite appreciative, thank-you!