I had my first experience TIG welding today with my new machine, and I have to say, this is pretty awesome. I am not a metal worker by profession...this is a hobby, but I can certainly see an addiction forming. In 6 months I have gone from owning nothing, to having a MIG and a TIG and various tools to facilitate the cutting and prepping of the steel. This board has been the single most valuable source for information and I thank everyone here for sharing your experiences and knowledge.
Having said that, I do have a question about something I experienced today. While TIGging two pieces of 1/4" steel plate butted together, i noticed that a portion of the bead kept "bubbling" up...similair to how a MIG weld will look when the gas is disturbed. I was using a 3/32 2% thoriated electrode with 100% Argon. I was not using filler at the time, but tried to fill later with ER70S-2 with no luck...the "pore" kept opening even while the weld pool was still fluid under heat. What was happeing?