TIG 304L what am I doing wrong?

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Hey all - building this turbo manifold for my car.  Machined the flange, got the schedule pipe in 304L and all is well.  However, the guy who makes the collector flange is able to do amazing welds.  Yet, I cannot seem to get the same results or similar!Here are some pictures, you'll know right away which welds are ours:Penetration seems good.  We were able to get the dimes look but it involved using no filler.  See the pic here:What are we doing wrong? Our setup is:Miller TIGSelector on 40 - 190 amps, with dial set to 60 (i think this is 60% duty)DC current, pedal control amperage, HF start.Straight 100% argon gas at about 25 cf/h2% thoriated tungsten pointed with about 3/8" out of #7 collet.309L filler rod.Guys please help me.  I am getting good penetration, welds seem strong, but they don't look very nice.  It will be getting coated anyway, but it'd be nice to develop some good welding skills on this project!Thanks!Jon
Reply:Jon, it looks as though gas coverage may be an issue (TOO MUCH), but really I think it's too much heat, added for too long. If you try to back down the gas flow to 15, and then try to work quickly, and use as little heat as you can get away with. When I do SS outside, in the open air, I get a fair dose of welds that discolor and blacken. Most times, it is wind pushing my gas out of the way...Boat work!!! But, if I am welding in a calm area and I see that, I try to get my foot off the pedal a bit. Try to pulse the heat, and time your dips. You'll see the blackening starting, so then you need to move a little quicker, or add more filler, or back off the heat....usually, for me??/All 3!!!!!! Good luck, hope this helps. Paul.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.
Reply:Originally Posted by RojodiabloJon, it looks as though gas coverage may be an issue (TOO MUCH), but really I think it's too much heat, added for too long. If you try to back down the gas flow to 15, and then try to work quickly, and use as little heat as you can get away with. When I do SS outside, in the open air, I get a fair dose of welds that discolor and blacken. Most times, it is wind pushing my gas out of the way...Boat work!!! But, if I am welding in a calm area and I see that, I try to get my foot off the pedal a bit. Try to pulse the heat, and time your dips. You'll see the blackening starting, so then you need to move a little quicker, or add more filler, or back off the heat....usually, for me??/All 3!!!!!! Good luck, hope this helps. Paul.
Reply:Getting a stack of dimes, is (to me) rather old school to me and is the last thing I worry about. A pulsing tigger can make a very smooth, fine line stack, etc.       The tight clearances and appearance on the collector, makes me wonder if it was welded in a glove box, chamber--especially the deep, close joints.1-clean rod and tubing with lacquer thinner, sand or polish tubing joint areas, wipe clean again2-your tube butt ends need to fit closely to each other, with some bevel on both ends, for this, I'd do a no-gap fitup.3-Use a gas lens--these not only can save on gas consumption, but really, really, really help stop oxidation in SS and aluminum welding. They pay for themselves, immediately.Side bonus on the gas lenses is the ability to run farther electrode stickout.4-Apparently, you've got too much gapping, too hot, too fast, and possibly too much gas flow (which can create more oxidation).5-I'd suspect that your welds will show significant melt and burn thru, inside the tube joints. This is not what you want.6-Make up some sample, test parts and set your weld parameters with those, before going back to the real thing. Consider back purging the joints prior to welding the outside--that's alot of hassle, and shouldn't be necessary.Blackbird
Reply:Someone else had this issue, and someone had suggested  keeping the filler closer when you pull it out. If you pull it out to far it will contaminate it, therefore contaminating the weld.Oh, by the way nice case! I have the same one! Attached Images
Reply:Yep.. What they said.Weld fasterturn down the gas flow to 12-15cfhclean the piss out of everythingfitup is everythingYou really need to backpurge these welds, or Solarflux them. Keep your filler in the gas coverage, OR don't use any filler at all. For these welds I would just fuse with no filler. You need a very good 0 gap fitup for this.Practice on some scrap for god's sake!Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:Looks hot maybe dirty, is that for a BMW motor?
Reply:Originally Posted by BurnitLooks hot maybe dirty, is that for a BMW motor?
Reply:i'm learning how to TIG on 304 at work... very easy, after you get the hang of it... they guys told me to work faster too... among MANY other things... remember to push, rather than drag, control the heat better... if you are getting too much heat, you have a few options... #1, move faster (can be hard to still control a good-looking weld-puddle)... #2, and my personal preference, turn the heat down on the welder. when i use the Miller ArcMaster at work, i tend to turn the heat down to near zero... on 1/4" 304/316 SS, i think i only run at about 20 Amps max... maybe up to 40 if i feel like i am in a hurry and i am able to get into a good rythem (spelling?). other than that, i find that the lower the heat you can use, the easier it is to control your "stack-o-dimes". i rarely use filler (i am still trying to perfect my basic skills), but when i do, i find that it is very important to keep the end of the filler rod inside the shielding gas cloud. if the rod leaves the cloud, it will oxidize, then when you add it to the weld pool again, it will contaminate the pool. also, make sure your tungstens are good and sharp. i find that the sharper they are, the easier it is to control the arc. as far as the gas goes, in another thread, it was explained that the coloration that is shown in the the SS welds is due to different levels of oxidation within the welds...http://www.weldingweb.com/vbb/showthread...=pretty+colorstechnically, the welds should be the same color as the parent metal when properly welded, however, if they are amber/gold colored, it is better than being blue, which is better than purple, which is better than black/dark gray. i have also seen pink(s)/fushia, but i don't know where it falls into that "ranking" system. i find that if i start seeing the blues or purples, it tells me to slow down my travel speed, and the welds start turing to golds/ambers. this allows the gas to stay over the area longer while the puddle cools, minimizing the oxidation. some guys crank the gas WAY up (about 40-50 CFH), and turn the amps to the max (about 90-200 depending on the welder they are using) and fly thru everything, but they rarely worry about weld appearance or strength... about 90% of our stuff doesn't need to be sturcturally sound... just water-tight.as far as the over-all integrity of YOUR welds, if you look closely, try to find a hole...no hole, no problem... if that is not sufficient for your needs, seal each opening... it's up to you how to do that... hook a bike-tire valve to one of the openings and pressurize the assembly... submurge it all underwater and try to find a bubble trail. no bubbles, no problem. the pressre test is more than likely going to be more pressure than the manifold will ever see under the hood from the engine.hope that helps.Later,Andy
Reply:Try turning the amps down. I weld 16 ga 304l with about 45 amps when doing a butt weld. Also try .045 welding rod. It melts quicker than .0625 filler.You will just need to feed it in to the puddle rather than dab it.And do all of the above. Clean, good fit up, back purge or Solar-flux. Dont use Solar Flux on the up side of the turbo. Back purge.Practice using as low and amp setting as you can and get the puddle to flow.mm135HTP Invertig 201 With water cooler9" Southbend LatheLots of hand tools.
Reply:For welding 304 or 304L, don't use 309 weld rod.  Use ER308LI r 2 a perfessional
Reply:I hope you are not welding by your computer. High freq off the tig travels and can mess with the electronics. --Gol'
Reply:Heat is the problem.  Do all of the above and remember that dipping the filer will cool the weld also.  John G.SMAW,GMAW,FCAW,GTAW,SAW,PAC/PAW/OFCand Shielding Gases.  There all here. :
Reply:Jon K,thank you for sharing the photos of some really terrible looking TIG welds.  Is this the very first attempt at TIG welding, or have you made good welds with this welding setup prior to trying these welds?If this is the first time, are you using 100% Argon gas, or did you hook up the 75 Ar- 25 CO2 from your MIG setup?If on the other hand, you have made good welds previously with this setup, I would check all the gas connections for leaks, and turn off the fan that is blowing away your shield gas.
Reply:Originally Posted by weldgaultHeat is the problem.  Do all of the above and remember that dipping the filer will cool the weld also.  John G.
Reply:Originally Posted by pulserIf the pool were properly shielded with inert gas, the heat input would not be a factor.
Reply:It looks to me like you are welding too slow, inputting too much heat. It's possible that you need to crank it up a little so that you can travel faster. It COULD be a shielding gas problem, but I don't think so, other than you need to backpurge.Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:I agree that you are probably pulling the wire out of the argon sheild, contaminating it, and then putting it back into the puddle. 25cfh isn't too much gas flow...unless you have a small cup...smaller than a #7.  I never weld with less than 20cfh.Put your tungsten in a bit more, leaving about 1/4" stickout.
Reply:Originally Posted by weldgaultpulser, what do you mean in saying heat is not a factor in stainless TIG welding????????  Please answer or he will be very confused.  John G.
Reply:Originally Posted by pulserJohn, what do you mean "heat is the problem".  You're right, if he didn't heat the metal, it would not oxidize, but then he wouldn't be welding would he.If you have very good inert shielding, it does not matter how "hot" you weld, the molten pool and heat affected zone will be protected and will not oxidize.The problem many of you are relating to, is that a hotter bigger puddle may require better shielding than a cold small puddle.  The hot weld shows up shielding problems more readily.The shielding problems could be due to a leak in one of the connections, a contaminated gas or the wrong gas (CO2 mix), turbulence from too high a flow rate, too little flow rate, too small of a cup, using a standard collet instead of a gas lens, excessive arc length (1/8" max), excessive torch angle, blowing away shield gas from breeze, etc.Contamination on the base metal or filler may also cause oxidation.  Water, oil, scale, etc.
Reply:Originally Posted by pulserJohn, what do you mean "heat is the problem".  You're right, if he didn't heat the metal, it would not oxidize, but then he wouldn't be welding would he.
Reply:Originally Posted by EngloidIf you heat a metal and it melts at 1800 degrees, even the length of time you leave it at that temp or how quickly it cools can greatly affect the properties of the metal.THere's a term called "jules" or sometimes spelled "joules."  It is a measurment of heat input that goes into the weld.  It takes into consideration not only the amperage, but the travel speed.  Lets say you fire up on a piece of 3/4" stainless plate with a tig torch.  You form a puddle, and don't travel.  THe puddle stays the same size, and after about a minute, you taper off the heat and stop the arc.  That metal that WAS melted will be significantly different from what it was to begin with.  It could even rust when the rest of the plate won't.If you look into heat treating techniques and the temps it takes, you will find that the amount of heat can drastically change the granular structures of the metal, well before it gets hot enough to melt.
Reply:Originally Posted by weldgaultI am glad you brought up heat input.  Joules is a heat input math formula, and it is: V X A X 60 Devided by Travel speed.  Example SAW: 30 V, 300 amps and 10" Travel speed = 54 Joules or 54000 Kj.  A perfect SAW weld in evereything that maters.  John
Reply:seconds in a minute, it is an absolute in the formula. John  PS look up Joules,a mans name that invented the equasion. Everyone should know this, it a must if you are worried about heat input.  I use 11 Joules on some jobs and 65 on others, only depends on what you want in the final results.  JohnSMAW,GMAW,FCAW,GTAW,SAW,PAC/PAW/OFCand Shielding Gases.  There all here. :
Reply:Oxidation, that's all I'm talking about.I don't care how much metal you melt, or how much heat you dump into the weld pool, it will not oxidize if there is no oxygen present.  Electron beam welding (EBW) is so insanely intense that the weld metal is vaporized and forms a keyhole, capable of penetrating some 6" deep, but this super heated metal is not oxidized because the welding is done in absence of all oxygen in a high vacuum.Question:  How do you eliminate oxidation (oxygen) in TIG welding?Answer:  Inert shielding gas.Jon K's welds are oxidized.  That is the result of exposure of hot and/or molten metal to oxygen.Sure, heat input affects the size of the pool and the HAZ, and affects grain size and grain structure, etc, but without oxygen you have not oxidation.  Metal has a melting temperture, unless the heat input is highly concentrated to cause vaporization as in EBW, you can dump in more and more heat, and all you do is melt a bigger and bigger puddle.Amps x Volts = Watts.Watts x Seconds = JoulesHeat input = Joules per inch = Watts / Travel speed (in inches per second).Quote from Engloid:  "Lets say you fire up on a piece of 3/4" stainless plate with a tig torch. You form a puddle, and don't travel. THe puddle stays the same size, and after about a minute, you taper off the heat and stop the arc. That metal that WAS melted will be significantly different from what it was to begin with. It could even rust when the rest of the plate won't."What you're talking about here Engloid is carbide precipitation.  Excessive time at temperature will allow the corrosion resistant Chromium in SS to combine with carbon in the steel to form carbides along the grain boundaries, and hence eliminate the corrosion protection in these "sensitized" regions.After your clarification, yes, I agree with you.  I guess I misunderstood your first post.
Reply:Hey Jon, what motor is that for? I am just curious, I worked for a BMW performance shop/SCCA Pro team for a couple years when I was just starting out.  I am a BMW nut
Reply:Originally Posted by Burnit I am a BMW nut
Reply:Jon K,so what's the verdict, have you solved your SS welding problem?What was the problem?
Reply:Originally Posted by BurnitI am a BMW nut
Reply:Originally Posted by pulserWhat you're talking about here Engloid is carbide precipitation.  Excessive time at temperature will allow the corrosion resistant Chromium in SS to combine with carbon in the steel to form carbides along the grain boundaries, and hence eliminate the corrosion protection in these "sensitized" regions.
Reply:google 'carbide precipitation' there's loads of info out there. here's a basic one written in plain english to get you started... http://www.burnsstainless.com/TechAr...s_article.htmlthe only 'rule of thumb' i'm aware of is minimizing heat input and using the L grades where possible.
Reply:http://www.weldingweb.com/vbb/showthread...+precipitation
Reply:okay... that answered my question. thanks guys. that helps alot. i appreciate it.Later,Andy
Reply:I was using too much heat in general.  I practiced running beads on a 1/2" plate of steel and am better.  But, Zapster is going to be doing me a huge favor and welding my manifold up fully since I am so short on time to get this project moving in other directions.  I can't thank Zapster enough.
Reply:Yes I am..I'm board.. ...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Jon is that going in an E36? Why no vanos?
Reply:Originally Posted by BurnitJon is that going in an E36? Why no vanos?
Reply:Originally Posted by Jon KHey all - building this turbo manifold for my car.  Machined the flange, got the schedule pipe in 304L and all is well.  However, the guy who makes the collector flange is able to do amazing welds.  Yet, I cannot seem to get the same results or similar!Here are some pictures, you'll know right away which welds are ours:Penetration seems good.  We were able to get the dimes look but it involved using no filler.  See the pic here:What are we doing wrong? Our setup is:Miller TIGSelector on 40 - 190 amps, with dial set to 60 (i think this is 60% duty)DC current, pedal control amperage, HF start.Straight 100% argon gas at about 25 cf/h2% thoriated tungsten pointed with about 3/8" out of #7 collet.309L filler rod.Guys please help me.  I am getting good penetration, welds seem strong, but they don't look very nice.  It will be getting coated anyway, but it'd be nice to develop some good welding skills on this project!Thanks!Jon
Reply:Originally Posted by William McCormick JrWhat size filler wire are you using? My guess would be 1/16" wire. That will cause that. The fellow that welded that probably used, 0.035 filler wire. I use 0.030 347 wire. Because of the low carbon you might have to use 308L I believe. But I would still use 347 for the strength.
Reply:Who cares?.. I'll do what I feel is right no matter what anyone says.. No dissapointments.. ...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:As you know by now, I like to question statements that are not backed up by some kind of reason, logic, or science.
Reply:Originally Posted by zapsterI'll do what I feel is right no matter what anyone says.. ...zap!
Reply:Originally Posted by pulserAs you know by now, I like to question statements that are not backed up by some kind of reason, logic, or science.
Reply:My only concern is that this manifold hold up   Zapster leaves me feeling like he has a ton of experience and seeing his pictures I have to agree.  I am sure he'll stand behind his work!
Reply:I am sure he'll stand behind his work!
Reply:Originally Posted by zapsterActually after it's done....I run and hide.. ...zap!
Reply:Im also very curious as to the 1/16 over .035 filler question, The smallest SS wire I have is .045 and that would be as small as I would want to go on a job like this.I have .035 mild wire but it never really gets used.Have we all gone mad?
Reply:Arc length is huge. This header I just did is 304L with 1/16th 309L filler rod: Not the greatest but I think it is decent considering it was using mostly stuff people are telling you is a no-no. The bottom line is don't make it too complicated. 1)18-25cfm and a #8 cup2)make sure none of it leaks3)sharp clean tungsten4)keep the tungsten as CLOSE to the work as possible. 5)use only enough heat to make the puddle a consistent, controllable size. Move steady.  6)clean the workpiece and filler rod before starting. That's it. Done. If you follow that and you can't get it to look decent with a few hours worth of practice, you need another hobby becuase it ain't rocket science.
Reply:Nice work.. But I'm gonna try to fuse as much of the tubing as possible...Flanges will require filler here and there.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.