Same as alumina cup ~15CFH

Got it working, had to jam 2 green o-rings up near the insulator and then tighten gas lens with cup installed. Seems ok now.

Only part I swap out is the glass cup for a thread on alumina cup and it works perfect. Has to be a problem with o-rings.

I am having same problem with this set. Narrowed it down a bit though, only happens with "pyrex" cup. pink cup welds perfect. Therefore it must be o-ring related.

I have tried to grind an extreme taper on 3/32 for low amp use with minimal success. We were taught in school that electrons travel on the surface of a conductor, (with a limited search Google now informs me that this is more true for AC than DC). Perhaps this would explain the reason correct tungst...