304 stainless position weld (stick)

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Need some advice, I just got the oppertunity to weld 30 inch dia. 304 stainless pipe flange on a spool pieice for a mag meter at a sewer plant. T he fitup was not very good, but doable. I am welding with stick 309 mol. 1/8" rod on DC + 95 amps. The problem is the inconsistency from one bead to the next. On one pass I can get the puddle to wet in good, and on the next the puddle will wet in but be way to convex. I use a very slight weave in the up position, a short arc, and in the overhead a short whip with a small circle the puddle. There is beads that look good, then I get the real high convex just ugly bead. I switched to AC, and DC -, without much difference. I got through this one without completly destroying our reputation as welders, but it took to long, and I did to much grinding to flatten out the weld and make another pass over it to clean it up, this made for to much stress and a long day for me! It looks like I have two more of these to do in a few days, so I have to get this problem solved. I have 23 years welding time for a construction company, but never had to do that much feild welding of stainless, but I love it and hope someone can give me some advice before the next two come up to weld. It is good to be able to call on the BIG DOGS for help, love this web site! THANKS.
Reply:304 is normally welded to itself with E308-XX. Are you welding 304 to plain carbon steel? Are you using a -15,-16 or -26 electrode? Are they fresh out of the box or oven? Stainless electrodes all have low hydrogen type coatings and must be kept dry.
Reply:Stainless stick rod is a tuff rod to use out of position on pipe.  Do you have to weld it with stick ?  Are you certified tig on pipe ?  I've had decent luck welding with stick from the 3 o'clock position up.  From bottom to the 3 o'clock its real tuff because the puddle doesn't freeze as fast as a 7010 or even as fast as a 7018.  Stainless rod is real "soupy".  Are you also having problems with pin holes ?  I did a little stainless pipe with stick the other week.  I was welding it on the bench (flat position) my amps were around 90 amps with 3/32" 309 rod. Try welding with 3/32" rod.  I know you're not putting in as much metal as 1/8" but with all the extra grinding you are doing, it'll probably be the same amount of time.
Reply:OK, I have scratch start tig on the truck, but the fit up that the non- welder left me and with the water in the bottom two percent of the pipe had me thinking that I would have better luck with the stick, and something I just remembered is that there was positive are pressure in the pipe, and I thought it would push the sheild away, it's not big air flow but it seemed to effect the start of the stick. The only problem I had with pin holes I can say was brought on by trying to get over creative with the technique. I was thinking the idea of the 3/32 is good because of the less heat input, and maybe shoot the joint with my laser thermometer and find the temp that makes the filler act more like when you start the welding, before things start to change. As far as the E308, I will try some on the practice bench and get back to you on how they worked. I was thinking of the L-16, what do you tkink befor I buy? And yes the rods that I was using were fresh that day. I want to thank you guy's for your ideas and I look forward to your reply, this is a real big help.
Reply:30" spool wouldnt jump out of the hangers  for you and lay flat???
Reply:I would say 1st pass with 3/32, then try the 1/8 on filler passes, then cover with 3/32 for appearance.  Some pinholes will weld out and don't need grinding, but of course large ugly ones might.  What is the inspection?  Do you have a remote?  You need one IMO.  Do you have a helper to turn heat and grind?  30"... you need one IMO.  If you're in there alone on a 30" stainless fitting with nothing but 1/8 rods, without a remote and no helper, then yea, its going to be a slow drawn out hard process.  If that was the case then I feel for ya man.Your judgment is going to be your best bet.  You sound experienced.good luck manLast edited by slowhand; 10-07-2010 at 07:34 PM.
Reply:Hey slowhand, thanks for the input. As far as the inspection, Im working for an engineer that trusts me, but I would like to keep it that way, so even if it is not perfect it needs to look like it is. The idea of the 3/32- 1/8- 3/32 is the thing to try, and try to not get in a hurry. I also think that I need to be involved in the fitting up of the joint, and will push for that. Now to add to your idea, Im thinking about closing the joint up with stick and then finish welding with the scratch start. That would take out the positive air flow problem. And yes I am alone, that seems how things are these days. It sounds like I have about three or four more days till the next one will be ready to weld, so I will be practicing hard. Thanks for the help, I will post what I learn.
Reply:Walking the cup up over it would make it look good I think.  But if you fill it with 1/8 you might need to grind off the humps and bumps first.  You wouldn't want to get hung up on one of them.   (I know I'd have a few knots on there) hahaGood luck manYes, do let me know what happens.