Invertig 221 Pulsed stick stainless

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Thought I'd throw this out and see what the pundits say.  I have a project consisting of partially re-tubing a stainless steel heat exchanger.  I had to cut off 8 half-round 4" pipes about 4 feet long to access the welded ends of the tubes.  Tubes are replaced, tig welded in, now it's time to re-weld the half-round pipes.  This is about 50 lf of horizontal weld, 1/8" wall thickness.  I have about 50 lbs of 1/8" very good Swedish 316 stainless rod I'd like to use.  I've never tried pulsed stick bu† this would seem to be a good application.  Thin metal, horizontal weld, high rate of deposition.  What should my settings be and is this likely to work?  Thanks.
Reply:Generally speaking, I've found background current in the 40-60% range and the same for the pulse duty cycle /on-time work pretty good.  Pulse freq is per your taste.  You can get a stacked-dime look if you use the lower settings coupled with a long period (low freq such as 0.6-0.8 Hz), but your timing (to advance/feed the rod on the peak of the pulse) and eye hand coordination better be spot-on. 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:Thanks Oscar, as i thought, the pulsed stick is a game changer.  Only problem is, following the instructions, i can only change frequency.  Pressing pulse button twice does not bring up P.du nor does pressing function twice bring up I.lo function.  Are the instructions accurate, is there some trick, or is my machine not cooperating?  It's working fine as is but I would like to get to the bottom of this.  I remember setting up a pulsed AC TIG program and it worked fine, just wondering what has changed.
Reply:You're right, I wasn't thinking straight.  The 221 only has Pulse Frequency available, and not the other functions.  I was thinking of one of my other machines. 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC