Mig welding 2 inch stainless. Help please.

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Hi, I was wondering if anybody has much experience mig welding stainless pipe.  I do have cert. for tig root / stick fill, cap, and stick root / stick fill, cap.  I've done a lot of mig for structural on carbon.  But never on pipe.  So I know I'm gonna need to bevel the pipe down to a knife edge, and probably go with a sloppy 1/8th for gap.  But I'm not too sure about settings.  I'm hearing i'll have to short arc the root in, then turn up for fill and cap.  So for short arc what am I looking at, say around 18V and say 200 ipm, a good ball park to start with?  And, not how about the fill and cap?  25V and 300 ipm?  All I really need is somebody to help me alittle bit with my ball park idea so that my learning process can be alittle quicker because we've got about 1000ft or 2" schd. 40 to do.  Oh, and the wire is 035.  Sorry about the jumbled up post.  I'm sure you got my drift though.THanks in advance.Matt P.S.  All the pipe will be welded on automatic rollers in the shop, and I'll be stick welding the field joints.
Reply:What's the wall thickness? A 1/8" open root is awful big for 2" pipe unless it was sched. 80. Even then, i'd still tighten it up a bit. The settings sound about right.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:umm, I dunno.  The wall thickness of 2" schd. 40 is probably around 1/4"..  Maybe just abit more.  I'm not really worried about the gap, because if it's alittle too hot, I can just turn it down.  But, ok maybe I should go with more like a sloppy 3/32, and around those settings?Thx.
Reply:One other question.  Will I have to back purge the pipe to prevent sugaring?
Reply:Yes unless you have a machine like a miller pipe pro. --Gol'
Reply:hello again,ok so the first few hours today were quite frustrating trying to get my damn welder set up.  but then I finally did get it.  thx, for the help, I appreciate it.  maybe i'll post some picture tomorrow if I remember to take some.  oh, and one other thing, I was able to put in the root wihout a purge, and there was no sugarig, or porosity or anything.  All they gave me was a pretty beat up old lincoln wire feeder, so I don't know how that works.  can anybody explain??shame on italian pipe manufacturers that can't make pipe to spec, and leave me to deal with 1/8th inch high low on each freakin side of the fittings!!!!  good thing this stuffs not xray, or my fitter would have been transitioning all day.matt
Reply:Originally Posted by Matt80hello again,ok so the first few hours today were quite frustrating trying to get my damn welder set up.  but then I finally did get it.  thx, for the help, I appreciate it.  maybe i'll post some picture tomorrow if I remember to take some.  oh, and one other thing, I was able to put in the root wihout a purge, and there was no sugarig, or porosity or anything.  All they gave me was a pretty beat up old lincoln wire feeder, so I don't know how that works.  can anybody explain??shame on italian pipe manufacturers that can't make pipe to spec, and leave me to deal with 1/8th inch high low on each freakin side of the fittings!!!!  good thing this stuffs not xray, or my fitter would have been transitioning all day.matt
Reply:Hey, diablo..  Ya,  it seems to be working fine.  I still haven't seen any sugaring or anything.  I've been checking every root before I close it up.  I'm obsessed with getting out my flash light and admiring alittle lol.  THX for the help, I've got that welder dialed in so much that I'm running a 5/32 gap on schd 40, and I'm dropping in the root just like its tigged.  So much fun.  Later.