12-31-2013 01:19 PM
I also use black iron pipe but my pipes are so old they don't look black anymore. I have a few 3/4" but mostly use 1/2". All my pipes are threaded both ends and with a few couplings I can make any length I want. If you use couplings get them in the electrical dep't, the wall thickness is much thinner than the plumbing ones. If you still want zinc buy electrical rigid conduit, much cheaper than Rockler. I cut some 3" squares of wax paper when I'm glueing and if the pipe is going to contact some glue slip a piece between the clamp and the glue, it prevents staining as well as keeping your clamps clean.
"Better to wear it out than to let it rust."