Originally Posted by GSWayne
I was shortening my centerstand, and after grinding off the paint for about a inch around the area I was going to weld, and then wiping it down with Laquer thinner for good measure, I was having trouble TIG welding it. The puddle seemed to occasionally bubble and spark. I was using ER70S-2 welding rod, a Weldcraft WP-20 torch, 13N09 cup, a 1/16" Lanthanated tungsten, 15 CFH of Argon, a Thermal-Arc 185TSW set for 100A max current, DCEN and foot pedal control. Test welds on 1/8" mild steel seemed to be fine. It would seem like some kind of contamination but I don't know from what. Any clues as to what I was doing wrong?
Did you have a hole somewhere to vent gasses? (I'm assuming it was a tubular part you were welding) Is there water trapped in the part causing steam to contaminate? Did you clean the inside of the tubing (If it is tubing)
Other suggestions would be to raise or lower the AR flow. Too high may be causing turbulence and allowing contamination or too low cfh will cause obvious problems. Did you try re-grinding the electrode in case it's been contaminated?
That's what jumps to mind anyhow.