I'm guessing that you're using a Scientific Systems IR job. Yes I've used C coils and they'er great. I also wish I had a dollar for everytine someone said: oh, yeah, I'll make you one. I'll call when it's finished. Don't wait. Sci. Sys. can make you a second round coil and by attaching them with bannana jacks, you can weld the tubulated one on, and then just move the power around to the other end to heat the nontubulated 'trode. MC