Stainless steel TIG advice needed

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Today was my first day welding stainless in the TIG class I'm taking at the local CC, finished up (for now) mild steel last week.Holy cow, I feel like I'm starting from scratch.  I can join the metal and the bead structure looks nice, but the bead is all grey, the HAZ is waay too big, and there is sugaring on the backside.  I'm using a Dynasty 350, 60 amps max (foot control) 1/16" 2% cerniated tungsten, 1/16" 316L filler.  14ga coupons.  I can fusion weld the stuff pretty well and keep a nice straw to red color, but when it comes time to add filler it all goes to hell.  If I keep the amps low enough so as to have a nice straw colored weld, I struggle like mad to establish the pool, and then when I do add filler it either seems to melt and drop into the puddle before I have a chance to dip it, or it actually balls up and doesn't enter the puddle but lays right in front of it.  Even then, I struggle like mad to manipulate the puddle and keep it moving.  Put some more amps into it, I can control it and add filler just fine, but it's getting way too hot.My instructor has said that my torch angle is too severe and needs to be nearly vertical, and that my tungsten may be too far from the workpiece.  The second part I don't think is happening, I've got it so close I'm contaminating it more than I ever have before due to touching the pool with it.  When he gives me a demonstration he makes it look so easy and his welds are so nice I want to just pull my hair out!  He's been a great teacher and next week I'll be back at it putting his tips to good use, but is there anything else I can focus on or correct in the meantime?  I only have 5 weeks of class left and I'm trying my best to make my lab time really count.  Today was a major struggle.Last edited by Wisco; 03-30-2011 at 02:58 PM.
Reply:I don't think you can get away from the sugaring on the underbead unless you use a backing gas.  The codes that I work with all require an underside gas purge for thicknesses less than 1/4".On the topside you might see if you can get a gas lens or bigger gas cup.
Reply:I would agree with you, except for the fact that my instructor can lay down perfct straw colored beads with no sugaring, using the same machine and setup I am, on the same material?
Reply:Originally Posted by obewanI don't think you can get away from the sugaring on the underbead unless you use a backing gas.  The codes that I work with all require an underside gas purge for thicknesses less than 1/4".On the topside you might see if you can get a gas lens or bigger gas cup.
Reply:Watch your instructor closely. Keep your torch close to vertical, and with a tight arc you will be able to create a small concentrated puddle. If you keep your fill rod away from the arc until you are ready to dip it, it can't melt off on you. When welding 14ga., you will need to keep your peddle maxed at the setting you are using in order to travel quick enough to prevent overheating and sugaring on the back side. Try adding less filler and advancing the puddle a little farther for each step and you should start to see results. You should consider welding without the foot control until you figure out what amperage setting gives you th ebest results. With experience, 14ga. will become easy for you, but 12 ga. would make things easier until you develop some skill.
Reply:2x on the short arc length providing a concentrated heat...puts the heat where you need it and you can move on.."struggling to establish a puddle"  could mean you are pouring unfocused heat into the work.puddle should come in 1-2 seconds. filler can also be used  to cool a hot puddle..try using 1/16 on something and then switch to 3/32 with the same heat and see how the puddle behaves different.Last edited by weldbead; 04-01-2011 at 03:24 AM.
Reply:This may not be what you are looking for, but when I was in welding school it was a much bigger help to have the instructor give me a demonstration and then have him watch me weld one right in front of him so he can see exactly what you are doing wrong and tell you instead of looking at the weld after and giving you a bunch of things you could be doing wrong.just a thought.