Newbie welding 2" SS Pipe

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Hello everyone.  I'm enrolled in the local pipe welding program and almost finished.  I am encountering a little difficulty on my 2" stainless pipe.  Here is my setup:  IdealArc250 set on 35ish amps, red tip 3/32" tungsten sharpened to a pencil point, 3/32 filler wire (308 I think?), #5 cup for walking method, pure argon purge set at 25 and torch set at 25ish as well.  I'm not positive on the type of stainless but its 2", about 1/8" thick or slightly more, and I polish the inside and out with a flapper wheel.  The fitment is a 30 degree bevel or so with a 3/32" gap or slightly smaller.  I run the root with a 3/32" wire and have tried the cap with 1/8" wire but the 3/32" seems to work better.Problem #1 - I seem to get fisheyes in my root.  Out of the three I have done I've had maybe 2 in each root.  Is this contamination?  How do I prevent it?  Problem #2 - Capping that sucker is hard!  I think I could alleviate some of my problems using a bigger cup on the cap.  Using the 1/8 wire for the cap doesn't seem to work well for me.  The filler won't lay down like I want it too so I switched to a 3/32 wire with better success.  I still find myself wanting to turn the heat up or going to slow and end up burning the pipe (oxidation).Thanks for any suggestions!
Reply:Originally Posted by JohnDaManHello everyone.  I'm enrolled in the local pipe welding program and almost finished.  I am encountering a little difficulty on my 2" stainless pipe.  Here is my setup:  IdealArc250 set on 35ish amps, red tip 3/32" tungsten sharpened to a pencil point, 3/32 filler wire (308 I think?), #5 cup for walking method, pure argon purge set at 25 and torch set at 25ish as well.  I'm not positive on the type of stainless but its 2", about 1/8" thick or slightly more, and I polish the inside and out with a flapper wheel.  The fitment is a 30 degree bevel or so with a 3/32" gap or slightly smaller.  I run the root with a 3/32" wire and have tried the cap with 1/8" wire but the 3/32" seems to work better.Problem #1 - I seem to get fisheyes in my root.  Out of the three I have done I've had maybe 2 in each root.  Is this contamination?  How do I prevent it?  Problem #2 - Capping that sucker is hard!  I think I could alleviate some of my problems using a bigger cup on the cap.  Using the 1/8 wire for the cap doesn't seem to work well for me.  The filler won't lay down like I want it too so I switched to a 3/32 wire with better success.  I still find myself wanting to turn the heat up or going to slow and end up burning the pipe (oxidation).Thanks for any suggestions!
Reply:Thanks for the advice.  I had thought about that too.  I had been just walking the cup and  pulling off once I reached the tacks, but now I started slowly walking the cup bringing the torch out.  The best way to describe a "fisheye" is they look like a small black dot on the inside of the root.  Like maybe the size of pencil lead.
Reply:I'll bring one of my pieces home so I can snap a pic or two of it.
Reply:Originally Posted by JohnDaManI'll bring one of my pieces home so I can snap a pic or two of it.
Reply:Turn your heat up by 20 amps minimum, bigger cup (7 at least, I'd be running an 8 or bigger if on hand) Is the parent metal the same as the filler?   If your going to be a welder then talk in schedule on pipe.  If you feather edge it you can weld it pretty much butted up hard, at least with very little gap.I'd rather be hunting........USE ENOUGH HEAT.......Drifting around Aussie welding more pipe up, for something different.....wanting to get home.
Reply:When you extinguish the arc, extinguish it slowly on the bevel wall, not in the root itself.  X2 on turning the amps up.  Your "burning up" of the pipe is more than likely lack of shielding coverage with a cup that small.
Reply:Finally I get to weld again!  It was a long weekend with the holidays and today I had another start back on the stainless.  I'm not sure on the schedule of the pipe but I'll figure that out tomorrow.  Dave Powelson was exactly right on the fisheyes.  I began to fade the flame out as I finished and the fisheyes all disappeared.  Thanks!  I think Wirehunt is right about the smaller cup not feeding enough gas to the pipe.  I switched out to a #8 cup with a gas lens and the pipe seemed to be able to handle the heat a lot better today!  Today I used a slight bevel with a 1/16" gap and 1/16" filler wire for the root.  Ran it at 40amps or so.  On the cap I used a 3/32" filler wire and ran it at 45amps or so.  I definitely need that little bit of extra heat for the cap or else it just wont lay down right.  It worked a lot better today.  I screwed up on the cap because I lost sight of the root pass (root pass was so flush it made it hard to follow) and capped slightly above on one side and below on the other.  Looks like McDonald's arches on the side lol.  I'll try turning that heat up to 50 or so tomorrow and see how it goes.  I will definitely bring it home so I can snap a pic or two and get some more pointers.