I have read in a previous post about striking on copper before using the new tungsten, also was mentioned in a text book (Modern Welding, c 1984) to keep a copper strip by the welding station. My concern is a wandering arc when first starting to weld, paticularly getting tack first
started. The arc circles down the side of the tungsten before settling on the tip, "pedaling " to max heat seems to hasten the process. Also the molten puddle seems to attract the arc, probably due to the higher emisivity of the hot metal ? Since my '83 vintage heliwelder is a transformer/rectifier machine, is it a balanced sine wave on the a/c ?
Thanks again, Jim
I think it was done to from the the ball on ac.Switch over electrode positive on a new ground tungsten,and it will form a ball right now when you hit the foot pedal.On mine I just don't have to mess with it.I am pretty sure its a sine wave machine.I could not prove it though.I do know one thing when its a squarewave machine they plaster stickers all over it telling you so,at least the ones I seen.Also on arc starting it helps when the tungsten is warmed up.
maybe your tungsten is too thick. but then again, if it was too thick, you'd have problems keeping the arc going. or maybe you're stepping on the pedal too slowly. try to get a feel for how far down you have to press the pedal while you're welding a good bead, and the next time you start the arc, press the pedal down to that same level whenever you want to start. you don't have to wait for the arc to get established and then put more amps into it...just start the arc hard and fast and the wandering shouldn't be a problem.
your machine is most likely a sine wave machine, since they didn't come out with affordable square wave machines until recent years.
I am using 1/16 zirc with at about 40A max on remote. Preheating the tungsten did help stabilize the arc start. Going to max pedal also helped but it's a lot harder on by nerves. I'm too accustomed to oxy/act flame, adding heat with a pedal is a little different ! After I get the feel for this machine, I'm going to try a newer unit with square wave and other toys just for fun. Safe and Merry Christmas to all. Thanks, Jim
another thing that might help you get accustomed to TIG welding is welding on 1/8" aluminum. it doesn't burn through as easily as a soda can and it's a lot easier to see what you're doing. you'll need a 3/32" pure or lanthanated, or zirconiated tungsten and around 160-200 amps. just don't get a thoriated tungsten...that's bad news for aluminum, but great on steel.
which makes me think of another point...you're using zirconiated tungsten...have you tried different kinds of tungsten? i've found pure tungsten to be pretty nice.