Self taught tig welder. Have questions on penetration Still very new to the art of Tig. When welding .120 wall square tubing in a butt joint I can't seem to penetrate through to the inside of the tube. The only way I can is getting really hot and then my weld looks like crap. I am grinding edges as well still can seem to penetrate into the tube. What am I doing wrong?  

Machine is an ahp 200 amps around 120+- and 3/32 tungsten and rod. 
