The easiest way to make one, is to forget it and just buy one. I've been doing a LOT of research on chillers and it seems that immersion chillers have the cheapest up front cost, but if water cost/usage is an issue for you a CFC will be worth the added expense. I seriously looking into buying...
I highly recommend not buying anything from the Beverage Factory. Two out of three of my orders were nothing but trouble. I won't do business with them again. They buy most of their parts from www.micromatic.com anyway. Micromatic has MUCH better prices, ship faster and overall better service.
Bleach IS bad stuff and must be used with care. Ever leave a sponge is diluted bleach. It melts it. I know someone who used straight bleach as a cleaner and had blistered skin for days. My wife accidently poured straight bleach on cat pee ONCE. Bleach and amonia do NOT mix well. She burned...