I had this idea kicking around in the back of my mind for a few years, but I didn't do anything about it. I'd like to thank two YouTube channels for inspiring me and finally getting me off the couch to start this project: Grant Thompson - "The King of Random" and AvE - "Arduino vs Evil". Both of these guys did some small hand-held carbon arc melting and casting in late 2014. Thank you.
I chose an XSPC EX360 radiator, three Thermaltake 120mm fans, XSPC G1/4" to 3/8" barb fittings, and a US Solar Pumps 12V 3GPM water pump for my water cooling system. Lowe's provided plumbing fittings and tubing. I welded the frame from the same 3/4" 1/16" wall aluminum square tube as the linear bearing The fans are pretty quiet compared to other stuff in the garage; I was surprised. I thought about using the Arduino as a thermostat for the fans, but decided against it because more sensors and wires seemed unnecessary at this point. Maybe I'll try that approach when I get around to a DIY TIG water cooler.
I used an old Android phone and the IP Webcam app to monitor things from the air-conditioned comfort of my living room. After the free IP Webcam app proved useful, I spent the couple bucks and upgraded to the IP Webcam Pro version.