Trouble starting arc (HF on alum.)

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I had a little project the other day welding up some disc brake mounts onto aluminum rims for my bros ultralight. Welds turned out clean but I had trouble getting the arc to start once the ball formed on the tungsten.  It would sit there with a small arc jumping across, I would stop and try again. Took a couple tries to finally get it started. Any advice would be appreicated.1/8" 6061 aluminum cleaned with stainless wire brush a joint.3/32 green tungsten130ampsAC freq 200balance 60% EN20cfh argon2 second pre flow14 second post flowMiller dynasty 200dxWelding outside in snow -3C, no wind.
Reply:Try red or a rare earth tungsten.  Cerated (orange) works pretty good.Sharpen it like for carbon steel.  Ditch the pure.Just try it......Its one of the benefits of having an inverter.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Where was your work clamp positioned in relation to your weld joint? Closer is better...especially with aluminum IMO.John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Originally Posted by Phil RI had a little project the other day welding up some disc brake mounts onto aluminum rims for my bros ultralight. Welds turned out clean but I had trouble getting the arc to start once the ball formed on the tungsten.  It would sit there with a small arc jumping across, I would stop and try again. Took a couple tries to finally get it started. Any advice would be appreicated.1/8" 6061 aluminum cleaned with stainless wire brush a joint.3/32 green tungsten130ampsAC freq 200balance 60% EN20cfh argon2 second pre flow14 second post flowMiller dynasty 200dxWelding outside in snow -3C, no wind.
Reply:Yes, it sounds like a poor ground. I normally weld with the ground clamp attached to my table only but on occasion when welding a light weight part it won't make good enough contact with the table and will either produce no arc or a weak one. I have another light cable with alligator clamps that I attach from the main clamp directly to the work. It gets the arc started and that then helps establish a better contact to the table.
Reply:I had the ground clamped directly to the work. The rims are just polished aluminum, perhaps I should have wire brushed for the ground too?Next time I have the welder out I will try the red tungsten.Thanks.