stainless tig help; too much heat?

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Hi everyone,ive been using my tig machine for a wee while now and have made a few bits and pieces but the most consistent problemstend to be with welding stainless. most of the time it turns out all grey. here is a few pictures of my latest attempt at welding a block off flange for my brothers car. the flange im pretty sure is 304 along with the plate and the filler is 316L. from my previous experience i think im putting in too much heat so this time around i pulled the current righ back to say 20-30amps at the most but it still turned out grey.heres one of my better attempts at welding stainless. here i used the pulse function and didnt use any filler.another problem i seem to be having with tig is getting a nice filet weld. most of the time it looks very untidy and wanders a bit and doesnt end up with a nice convex profile. i cant seem to get the weld pull to advnace and have to pull it along by dipping the filler rod at the tip of the puddle. ill try to get some pics of what i mean tomorrow.
Reply:What is the Gas and flow rate, tungsten, tungsten inside or outside the nozzle, how far is your nozzle from the work and what is the amps and volts.  JGSMAW,GMAW,FCAW,GTAW,SAW,PAC/PAW/OFCand Shielding Gases.  There all here. :
Reply:Not enough amps and too slow a travel speed.Filler never flowed out in the bead I see (too humped).This is a place where pulse, properly used, can be of great benefit.  High peak to quicky create the puddle/melt filler, and background amps to keep the average heat down.Staying in one spot too long, waiting for puddle to form, will cause that grey bead in stainless.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by SundownIIINot enough amps and too slow a travel speed.Filler never flowed out in the bead I see (too humped).This is a place where pulse, properly used, can be of great benefit.  High peak to quicky create the puddle/melt filler, and background amps to keep the average heat down.Staying in one spot too long, waiting for puddle to form, will cause that grey bead in stainless.
Reply:Are you useing a puging block?
Reply:Originally Posted by weldgaultWhat is the Gas and flow rate, tungsten, tungsten inside or outside the nozzle, how far is your nozzle from the work and what is the amps and volts.  JG
Reply:Your stick out can be reduced to about 3mm and the distance of the tip of tungsten to work can be reduced by half.  The further you are away from the work your arc will get hotter resulting in overheating the SS and with tig you controll the heat with the foot pedal not arc length. As you advance the torch you should be pushing the puddle forward and adding filler to maintain the size of the puddle to a consistent width.
Reply:Have you tried a gas lense?  Travel is to fast to much heat and not enough coverage in the gas envelope.
Reply:Originally Posted by thermalfusioneng.Have you tried a gas lense?  Travel is to fast to much heat and not enough coverage in the gas envelope.
Reply:You can setup that cap weld edge to edge and do it with no filler, that is best for stainless steel.You can use a touch of filler wire, if you create a low spot. You could do it fast or slow, as long as you properly heat it, and move with the heat, it will come out nice. If you like to weld slow, very little heat, a lot of preheat, until the metal bonds by itself. If you like fast, that is fine too, a little more heat, and probably more attack angle and away you go. That will give you the best color the best penetration and least burnt stuff. It will look like they poured it in a mold. You should run some backup gas behind the weld.        Sincerely,             William McCormick
Reply:I run the tungsten a millimeter to two millimeters off the work for most stainless stuff. Unless I am lifting and moving. You could stick it out 5 millimeters or more depending on what kind of weld it is. If you are doing a fillet in the acute angle of a pipe joint you might need it out very far. But for that type of outside corner weld you would probably like to be aiming pretty straight down on it, not much push angle so you do not need much sticking out.        Sincerely,             William McCormick
Reply:You know all my years welding cryo stainless and aluminum, I don't ever recall welding over 90amps no matter how thick the material on stainless. I always had good full pen fusion, no matter what the rod or mat. On steel I usually run wide open so now is the case with stainless.Your application doesn't really call for a pulse but if your learning, I'd start with aluminum. Once you get that pretty you can apply it to stainless. Good luck,have fun.
Reply:Honestly, if your running only 20-30 amps then you cant be moving fast enough to get that kind of discoloration and surface oxidization.  You can actually see flakes of oxide starting to peel off in some spots.  However, if you were moving so slow as to be able to get the material that hot there should be plenty of burn through on the inside as well which I do not see. If it wasnt for the weld you did with pulse, I would say its a problem with gas coverage.  Is there any chance you were in a windy environment when doing the ferrule cap, and not when you did the pulsed weld?Have we all gone mad?
Reply:at a guess i would say i was moving at about 3/4 of a second between moving on so focus for 3/4 second to advance the pool then add filler and move.both welds were done in a closed garage so the wind shouldnt of been a problem.are gas lenses universal fitment like the cups and the collets? the reason i ask is because i have a chinese welder and not a miller or anything mainstream like that.
Reply:So you don't think there is anything wrong with your technique/set up? A gas lens isn't going to help you.
Reply:Originally Posted by justinsueat a guess i would say i was moving at about 3/4 of a second between moving on so focus for 3/4 second to advance the pool then add filler and move.both welds were done in a closed garage so the wind shouldnt of been a problem.are gas lenses universal fitment like the cups and the collets? the reason i ask is because i have a chinese welder and not a miller or anything mainstream like that.
Reply:Originally Posted by Jay OSo you don't think there is anything wrong with your technique/set up? A gas lens isn't going to help you.
Reply:20-30 amps is way too cold.  I put the root in 2in sch 10 stainless at 60 and thats open butt.  Turn your heat up to at least that and try again.  You need the metal to flow so you can move with it and that is your problem.  You are trying to weld way too cold and therefore transferring more heat to the work since the travel speed is too slow.  Case in point - I've been welding a lot of 6 inch sch 40 carbon pipe lately and was running a consistant 190-205 amps with a nice narrow heat band on the weld.  Well I decided to turn it up to 220amps the other day and believe it or not the heat band was smaller on that weld.  Yes I was welding a good bit hotter but my travel speed was much faster as well hence the narrower heat band.  The same applies to stainless.  Put yourself a medium or jumbo #8 gas lens on the tig head, use a piece of razor sharp 3/32" red tungsten, have some 1/16" filler wire handy, turn the machine to 60-70 amps and more or less fuse weld it while adding a slight amount of wire as needed.  Travel fast. You'll get your color then.
Reply:Oh yeah, almost forgot . . . CLEAN IT before you weld it.  Looks as if you never cleaned either part before welding it.  Take a flapper wheel or something similar and buff the metal a bit.
Reply:todays efforts:the top is a pule no filler, middle is a filet weld beileve it or it its actually one of the better ones I've ever done but its still crap. the bottom is a no pulse with fillerthis one here was no pulse with filler but sort of pushing the weld pool rather than sitting there waiting to form as i usually do:this one here i turned up the heat to 40 or so i think and used filler and moved quicker.back shot of the filet:back shot of the pulse:thats all i could get done before i ran out of gas.JohnDaMan do did you add filler when doing ur 2" pipe at 60A? how much of a root gap did you have when you do that?and have sort of been cleaning it mostly by just grinding off the burr and wiping it down with some acetone. how far away from the weld should i be buffing/grinding the parent metal?
Reply:Yeah I use a 3/32" gap and 3/32" filler wire then use 3/32" wire for my cap.  Usually I have to turn it up a few amps for the cap.  Do you have a tiger paw?  If not get a 120grit tiger paw and use that to buff the metal before you weld it.  You dont have to go crazy with it.  Just lightly buff right around the area you will weld.In the pics of your new welds still traveling too slow.  All that black stuff on the backside of your weld is called sugar.  Turn the heat up more and travel fast.  When you can get the fillet weld down with no sugar on the backside (just a heat line from the weld on top) then you're getting somewhere and can start with the cosmetics of the weld.  Until then practice on traveling faster and watching that puddle.
Reply:No need to "buff" the material with a sanding wheel, only time you usually need to clean stainless is if there is visible dirt/oil on the surface and even then its just a swipe of a rag.Have we all gone mad?
Reply:You are new, no doubts about it, try laying your cup on the work. Adjust your tungsten so that while the cup lays on the work ready to weld, at a twenty degree forward push angle, the tungsten is 1 to 2 millimeters off the work. No pulse, 13 cubic feet an hour that is 368.11 cubic liters an hour, that is your minimum. That is also six and a half liters a minute. That is a minimum, however stainless likes a gentle flow. You will see a difference right away.I do not know what your post flow is set to, but if you set it to 30 seconds and your tungsten is turning colors then up the gas. The tungsten should stay bright and shinny like chrome if you have enough post flow time and you should. When you go to tack, lay the torch on the work like stated above. Aim the tungsten into the crotch of the outside corners that are edge to edge. And just turn the machine on slow and moderately low. Do not move the torch, or adjust the torch, nothing. Just wait for the metal to bond by itself. I would not add wire while you are first mastering this. When you have it tacked, start at the beginning of the plate, or just in enough so you can rest the cup. This is just practice. When you get your puddle, without adding wire, I would raise the torch slightly, and move ahead very slightly, rest the torch down, and you will be ready to lift and move again. In very small increments. The weld might even be silver or gold depending on how well you do that.        Sincerely,             William McCormick
Reply:William,Anyone who knows what they're doing, reading this post, would come to the conclusion that you are full of BULL.Lot of jibberish that really said nothing.If he's using 30 seconds of postflow for the amps he's welding at, he's using too dang much.Would it be too much to ask that you just comment in English so most of us can figure out what you're trying to say.You say not, but I swear it seems that your objective is to "confuse" new welders.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Use 1/16 wire a gas lense gas at 35 for good coverage and a #7 cup. You puddle should have what looks like a little bubble spinning around in your puddle. That little spinning bubble I guess should be spinning about 5 to 7 rotations per second. Welding stainless is a art not many welders never seem to master it.Rule of thumb, set your heat 10 degrees cooler than the thickness of you material. So for .065 materialset your machine at? - - - - 55 amps and so forth . use the material thickness rule for stainless and thin gauge materials you cant go wrong.Thats enough for me, after seeing those welds I think I'll retire and get into teaching.Good luck Amigo and like you said practice practice practice.thermalfusion,That's about the biggest bunch of BS ever assembled in one thread.Have you ever welded SS or did you "just read about it in a book somewhere".  If it was a book, it must have been a "comic book".This thread contains enough "bad advice" to throughly confuse anyone.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Better put the waders on....it's getting deep in here.http://all-a-cart.comWelding Cart Kits and accessories
Reply:Paul wins. Nice suit........ Thread needs to stay on track. Quit posting nonsnese, and quit attacking each other. The good, solid advice is already given, so I am closing this one too.Jeezus, makin' me earn it this week.....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.