Welding Tips and Tricks

Hello, I have a Lincoln 300 300 TIG, it welds perfect on all steels so far, the stick is smooth as glass, but when I try and weld aluminum it does something funny, I get a puddle that's sooty then all of a sudden it the machine makes a almost unnoticeable little buzz noise and then the puddle cleans right out perfect, then after a few seconds it goes back to sooty puddle. sometimes I can get three inches of perfect puddle then other times it will only give me one dime? I set the points to 16 the machine says 10 but at ten no clean puddle just sooty. I am working on t 6061 scrap ultra clean 4043 rod pure tungsten 100 argon gas. the machine was free came with all the extra's and I love the way it weld's. I am a certified TIG aluminum welder at a foundry, so I know how to weld aluminum. thanks for looking Byron.

The cleaning action of a variable square wave would be a definite advantage. Straight sine wave transformer machines are inferior in that case. On your machine, you have to be working with aluminum that is ultra clean, both base metal and filler. Not saying anything in a negative sense, you have one of the best sine wave transformer machines out there. That may be your issue. Or, maybe check all your fittings, especially at the gas solenoid. Hope that helps.

Hello, once again thank you for your time reading and commenting, I figured it out now it welds perfect stack of dimes with aluminum. turns out and maybe someone can post and I will do research as well. all I had to do was warm up the aluminum once I got it nice and warm the cleaning action was killer and it welded like a dream tried some cool pieces and nope just sits there sputtering soot puddle, put the propane torch on it and wammo sine wave super cleaning action. go figure that was welding 1/16 and 3/32 thickness sheet aluminum butt or lap joint or just laying some beads on the surface. so glad I got the aluminum going cause I got a trailer to weld.