Trouble with 304 TIG

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Had an issue today TIG welding some 304 stainless for a tank. Dynasty 350 at 200amps using pedal1\8" platefull open corner308 filler 1\16 and .0451\16 red tungsten-sharp tipgas lense at 15cfhThe problem I was having was the puddle would not advance in any predictable manner.  Normally when you dip and move the torch forward the puddle follows.  Instead the puddle wanted to stay behind like a cold weld and only melt the edges.  Increasing the torch angle didn't help.  More amps didn't help either.  If I managed to get the puddle to advance, once I added filler it would wick away towards the last dip and build up.  Or jump towards the top edge ( even with a downward torch angle ).  I have never ran into an issue like this and I'm stumped.  Changing amps up or down didn't help, increasing/decreasing torch angle didn't help, different sized filler didn't help.  Heck, I even turned the pulser on and pulsed the puddle at 400pps to try and push it forward.  Nothing helped the situation.I pride myself with my welds and always lay down the best I'm capable of.  But this crap has me feeling like a newb and looks like complete a**.  Any help would be great.  Thanks
Reply:yeah takes practice. try the smaller filler more heat at first then taper off. stainless its really confusing at times to control the puddle. I sometimes stick the tunsten out a few mm more and use more torch angle to push the puddle, but then you have less gas coverage and its not ideal but it works
Reply:Pictures of the tankTypical welds I usually produce, except today apparentlyThe welds that wicked to the edge all went towards the top plate with the pipe nipples.  Wondering if arc blow is possible somehow.
Reply:JR,Nice look'n fit up.   That should weld out nice.    Have you tried hooking the rod to the puddle and then keeping it attached to the leading edge of the puddle as you move forward?   It takes a little more heat and you have to keep a steady pressure pushing the rod into the puddle.
Reply:Any pictures of the issue? Sometimes if you aren't getting enough shielding the puddle won't do what you want. On outside corners you may need to push a little higher CFH with a shorter stickout.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:whats that tank for. I weld stainless tanks like that all the time. usually about 3/32 thick or a bit thicker I guess. Fuel tanks. My setup and technique that works for me. 3/32 red tunsten, 3/32 filler rod, gas set at 30cfh(overkill but no ill effects) no gas lens. stick out is on the longer side and angle the torch a bit to face the puddle and push it. Keep whatever your welding going down. Meaning the welds should be going downhill at least to some degree, stainless flows way better this way. keep really tight arc gap and make sure to light up hot and then as soon as your first dip you should be moving very fast. pulse will help 40pps or so but Ive never even done it pulsedanother thing those tacks will completely ruin your day i know the feeling of running over nasty big tacks like that. the puddle will get cold and wander every time.all tested at 15psi, military fuel tanks. not pretty but I dont get paid for pretty welds lolLast edited by taizer; 12-17-2014 at 12:54 AM.
Reply:Yes, I tried lay wire.  Was the only slightly successful welding that happened on the corners.   But even then the puddle wasn't acting right.  I'll bump the gas up today and see if that helps.  As for the tank, I don't know what its for.  The parts were layed on my table with a simple drawing and I was told to make it happen.  I believe I remember hearing something about salt water going thru it.I've got roughly 120" of weld left on this part.  I'll try and get a picture of the welds.Last edited by JRwldr; 12-17-2014 at 05:28 AM.
Reply:JR,I think your problem probably has more to do with your tungsten angle than anything else.   With that laying flat on the table it just makes for an akward angle to try and hold your wrist at and move smoothly down the joint.   I'm not saying it can't be done you're just making it harder for your self than it needs to be.   Get some thing to prop under the edge of that tank and get it up on an angle so you'll have a better attack angle at the weld seam.  You might need to clamp some thing to the table on the opposite side so it doesn't slide away from you.   Not saying you've got to get it all the way up on a 45 to where you're welding flat but tilt it up some.   Especially if you're trying to use the tank it's self as a support for your wrist or forearm while you weld.The other thing is to come up with a separate support for your torch holding wrist / forearm to where it's at a comfortable angle and can move freely and smoothly while you're welding.   I've used milk crates, coffee cans, different size blocks of wood, short pieces of other material, the edge of the table, etc. etc.
Reply:Pull your pulse rate to 80PPS on default settings which is 45bg and 25time. At least it will cease to be a watery puddle. I have recently found er347 to be a compatible filler in lieu of 308L. Also too much gas is as bad or worse than too little. At 15cfh I assume you are using a #5 or #6. I would go up to a #7 or #8, and pull your flow to 20cfh. 3/32 red needle sharp is my favorite for this thickness, but I suppose 1/16 is fine. 1/16th filler sounds good to me. Keeping your filler in the gas stream is utterly important. I all adds up.Last edited by shovelon; 12-17-2014 at 12:41 PM.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by HT2-4956JR,I think your problem probably has more to do with your tungsten angle than anything else.   With that laying flat on the table it just makes for an akward angle to try and hold your wrist at and move smoothly down the joint.   I'm not saying it can't be done you're just making it harder for your self than it needs to be.   Get some thing to prop under the edge of that tank and get it up on an angle so you'll have a better attack angle at the weld seam.  You might need to clamp some thing to the table on the opposite side so it doesn't slide away from you.   Not saying you've got to get it all the way up on a 45 to where you're welding flat but tilt it up some.   Especially if you're trying to use the tank it's self as a support for your wrist or forearm while you weld.The other thing is to come up with a separate support for your torch holding wrist / forearm to where it's at a comfortable angle and can move freely and smoothly while you're welding.   I've used milk crates, coffee cans, different size blocks of wood, short pieces of other material, the edge of the table, etc. etc.
Reply:Here is a picture showing the weld.  Looks like crap and I'm not happy posting it but it is what it is.  Haven't had a weld look this horrible since my first semester at college. Tungsten angle was spot on every time I had the problems and I had actually elevated the part making the weld a flat position  weld.  In the picture, it was a straight run, dipping filler.  No lay wire or torch weave.  As you can see the puddle did as it wanted.I was using a #7 cup with gas lense at 15cfh.  Bumped the gas up but that actually made things worse, so I settled back at 15cfh.  Tried changing more settings but nothing changed.  Getting aggravated and about near desperate, I decided to change gas lenses.  Didn't have any more 1/16", so I changed out to 3/32" with a red tungsten and blunt tip.  And what do you know, I can weld again.  It seems that while 1/16" tungsten could most certainly handle the amperage, it didn't have enough of an arc cone ( arc width ) to act properly with that joint.   It couldnt melt what it needed to and that now explains why everything behaved like a cold weld yet was very hot.  I learned something new today and was able to finish the last 20" of weld with decent results ( compared to earlier) and normal settings.  Here's some pictures of the final part and some weldsLast edited by JRwldr; 12-17-2014 at 07:36 PM.
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Reply:Serious improvement. Are you sure the collet and collet body are in good shape?  Could have been choking off the gas flow or something else.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:that makes no sense but whatever it worked lol
Reply:I'm sure both are in working shape.  Immediately after finishing this tank I had to use them on some 0.65 stainless tubing.  Nothing but gold shiny welds.
Reply:An outside corner joint well get you every time if you aren't on it all the time. A #12 cup with gas lens helps and if you were to weave it so the puddle rolls over the edges so they tie in, you'll get it. I would bump up to a 3/32" thoriated tungsten and push the hell out of the torch. Should come out silver all day.-Hillbilly
Reply:Originally Posted by taizer
Reply:JR,Glad you got your mojo back.   I'd say that over all it turned out pretty decent looking.
Reply:JR,This is the last thing I welded up that's kind of similar to your tank.   I used a 1990's model 250 Syncrowave, 1/8" red tungsten sharpened pretty pointy and 1/16 and 3/32 308L filler.   Not saying I didn't do some daubing in a few places but for the most part these welds were all done with the lay wire technique.    The reason the weld on this corners is so wide is because the one plate got cut to small and I had to scab in a piece of 1/4 flat bar on two corners to make up for it.  There's actual two smaller welds side by side underneath it.  I didn't like the way that looked so I covered it with a wider free hand weave to pretty it up.
Reply:I know the picture is kind of blurry and you can't see the welds that good but this is the lid to that tank.  I used the "lay wire" technique on them.   May be I'm just getting old and lazy but all that constant daubing just seems to me like to much unnecessary work for welds on things like this.   Plus I think the lay wire technique allows me to get a given volume of weld metal on some thing quicker which in most cases results in less over all heat input into the part.  Here's another out side corner on some thing else done with a free hand weave and the lay wire technique.  There's at least one (may be two, can't remember for sure) passes underneath what you see.   I guess I should mention that all these welds were done with a WP-20 torch, gas lens and #8 cup.Last edited by HT2-4956; 12-18-2014 at 01:25 PM.
Reply:Originally Posted by MikeGyverIs that a solid pin? What's it for?
Reply:taiser,I'd like nothing better than have to weld out 50+ of those fuel tanks (especially if you fit them up).   Hot, fast and with a tight arc using the "lay wire" technique would be the way I'd go at it.
Reply:yeah you would probably do better than me. welding them free hand is not my thing. I tried laywire and failed horriblythe fitment sucks in most spots, but they are all purged so its not too bad.
Reply:i was going to ask about your  purge. what you were describing is similar to what i run into if a purge pressure gets too high.bosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin