From out of the blue...
If you are a woodworker, you know that you don't need a diamond hone to make your tools sharp, good sandpaper will do and if you are working on the cheap for dark room stuff, try using beach coolers for water temperature control. It is hard to beat the price and time investment is small.
PS, I made my "sink" (more so a splashway really) out of Luan subfloor material and 1x4 pine, coated with Polyester resin. $40, works fine!