TIG Destructive Testing 1/4" Single Pass

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Ok, I got the 20 Ton press setup again and decided to test some of my TIG welds.I did two types of fillet welds.  1. 3/32 Filler on a 1/4 MS with the edge beveled, single pass.2. 1/8 Filler on 1/4 MS with the edge beveled, single pass.I used ER70S-2 wire, 230A (not full pedal), 3/32 Tung, Gas Lens, Walked the cup.I have attached the photos for the 1/8" filler single pass in the post and the 3/32" filler single pass in the next post.The 3/32" filler did not hold up as well and the 1/8" as you can see from the side view after the brake.  I had the press mashed down about as hard as I could go before the 1/8" broke and on the 3/32 no contest at all.  It was a quick death as you can see from the minor bend on the side view.Please tell me your thoughts.  Both weld beads were just about the same size and thickness.  On the 1/8" filler it took a little longer I think because I have to melt the thick wire in.  I was able to move a little faster on the 3/32 so I think I got less heat in the metal.Thanks in advance.Last edited by David R; 01-13-2008 at 07:20 PM.Reason: PicsBuild a Barstool Racer at BarFlyRacers.com!
Reply:I have attached the photos of the test done with the 3/32" filler.  For more info, read the first post.Build a Barstool Racer at BarFlyRacers.com!
Reply:Excellent!Thank YouDavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Nice job.What about bending the other way towards the weld?  That should allow you to see if there is penetration at the root?Just a thought.BrianLincoln Mig 215Miller 211Victor Torch SetMiller Maxstar 200SDMiller Syncrowave 250DX Tig runnerMiller Trailblazer 302 running on LPMiller Extreme 12 VS SuitcaseEllis 1600 BandsawMiller xmt350 CC/CVLincoln Vantage 300
Reply:Originally Posted by BSOKNice job.What about bending the other way towards the weld?  That should allow you to see if there is penetration at the root?Just a thought.
Reply:BSOK,I did a test that way without the bevel and it broke.  I do not think I am going to get full penetration with a single pass doing a fillet weld on 1/4" mild steel.  The most I could see from the ends was about 50% penetration.I did do a bend test on a 1/4" fillet weld which I welded both sides and no break, just bent it all up so I am assuming the welds are strong.I am doing these tests because I am going to be building a tubing bender and most of the frame is 2" x 2 x 1/4" wall so with welding all four sides it should be strong enough to hold up to the stress if I use the 1/8" filler.I do not know if it is possible to do any better on the 1/4" other than a deep bevel and multi pass.Build a Barstool Racer at BarFlyRacers.com!
Reply:I figured you did a test the other way as well.  I was curious to see what your results where.  Full penetration on 1/4" is not likely and may not be required based on joint design and requirements.  Especially if you can weld both sides.  Good luck with your project.BrianLincoln Mig 215Miller 211Victor Torch SetMiller Maxstar 200SDMiller Syncrowave 250DX Tig runnerMiller Trailblazer 302 running on LPMiller Extreme 12 VS SuitcaseEllis 1600 BandsawMiller xmt350 CC/CVLincoln Vantage 300
Reply:Originally Posted by David RExcellent!Thank YouDavid
Reply:malich,I think the answer for you is that with your skill level and general welding procedures, you need to use the 1/8 inch filler and bevel-prep the edges when you TIG 1/4 inch thick material.  Weld both edges to get the best strength of your weldment.I think you skimped a little on the bevel prep though.  Bevel a little more and leave closer to just a skant 1/8 inch land (unbeveled area) in the middle of the plate.  When you make the weld pass on one side, the weld should just melt through to the other-side bevel.  Then when you weld on the other side, your weld will melt into the inside of the first weld bead and you will have 100% penetration and fusion and your piece will be as strong as you can get it with that size base material.With the way -both- welds failed at the top of the weld bead on the T joint, you either had some undercut going on with both weld beads and/or your press loading test was set up to shear the vertical plate near the top of the beads.  If it was undercut, work on directing the arc a -little- bit more onto the base plate and wash it up onto the vertical plate.  If it was just the way your press loaded the test, so be it.
Reply:I don't think a T Joint needs to be beveled unless you don't have enough power.  That is why I use them in tests.  A bevel in plate has to be ground.  A fillet is pre prepped.  Just remove mill scale and weld.  The fillet should be as big as the plate.  It it takes multiple beads, then so be it.  Rule of thumb.  1 amp for every .001" steel for ONE pass.  Did you use full 250 amps?   The fillet should have 1/4" legs on both sides and be at least flat across the top of the bead.I think a full size bead should not break even in a root bend.  I could never do it in one pass.Gonna try it tomorrow If I get time.  Only problem all I have is 3/8 X 4 plate.  So I will need 375 amps to do it in one pass.  Malich, I'll weld em, you bend em  OK?DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Hi Moonrise,Thanks for the reply.I think you are correct on beveling more so I only have 1/8" left to burn through.  The only problem I can see if that getting the heat and penetration into the horizontal part is harder because the heat rises and there is no bevel on that part.  But then again, it tore out of the top of the weld, so who knows...Not sure about the press setup.  I just put it in there and smashed it.  I will take a photo of the press setup on the next test.In the past I have migged 1/8" fillets and smashed them in the press the same way and nothing broke.  I am thinking part of the break has to do with the metal thickness since you can not bend 1/4" and much as 1/8".  But also there is some failure in the welds, but from the ends mostly from what I can tell because I did not get a good fuse on the 3/32 fillet weld on the end and a small bead at the start.Build a Barstool Racer at BarFlyRacers.com!
Reply:Originally Posted by malichHi David,I guess what I was trying to determine if my welds were good / strong.  I am not sure by you saying excellent was for a good weld or me being able to break them?  Thanks!
Reply:Thanks David.Let me ask you this...  Is it possible with more amps to get full penetration on 1/4" with a single pass or not.  I would think the puddle (if even possible) would be messy and difficult to control.What is the advantage (besides aluminum) to have the additional amps / larger machine?  My 225PT only used about 1/2 to maybe 3/4 pedal to do the 1/4 welds.Thanks!Build a Barstool Racer at BarFlyRacers.com!
Reply:Oh, and as David mentioned, single pass welds for steel rule of thumb is 1 amp per 0.001 inch thick.So for 1/4 inch thick steel pieces, you need 250A of juice.  Give or take a little.Or you have to run multi-pass, maybe with some weaving on the cover/cap pass.And again as David reminded us, the usual size for a fillet weld bead is the same size as the base material.  So for 1/4 inch plate, you generally want the weld bead to be 1/4 inch up and 1/4 inch out and to NOT be concave (you do not want the weld bead to dip down, you want it to slightly curve up and be 'proud' of the area).And about the "heat rises" thing.  Sort of, but usually not fast enough to make much difference compared to the heat of the arc itself melting the steel.Looking closer at your pics, now that David mentioned the bead size, I think your beads and amps were on the low side of things.
Reply:What I quoted was a rule of thumb.  I machine set up to do that all day may achieve it.  I am going to try it.  It would be a large deep penetrating weld.   I see no real use for more than a couple hundred amps for tig because as you get bigger there are much more efficient ways to weld.  Mulitpass needs less amps as long as you get good fusion on every bead.  I do most of my tigging with a TA Arcmaster 185.  Once I tigged some parts at 220 amps with the V350, but only one job.PT225=nice machineDavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Forget that "walking the cup" idea.Keep the cup away from the metal, otherwise it leaves discontinuities in the surface of the metal.The way to really see what is going on is to weld your T joint on both sides.Then cut the weldment transverse to the weld with a abrasive saw or metal cutting band saw. Sand the face of the crosssection and brush on some blue machinists ink. Then wipe clean but leave just a little ink to show the depth of penetration of the root of the weld. Use a magnifying glass.The filler wire that would be easier to use would be .045 diameter.
Reply:Originally Posted by MoonRiseOh, and as David mentioned, single pass welds for steel rule of thumb is 1 amp per 0.001 inch thick.So for 1/4 inch thick steel pieces, you need 250A of juice.  Give or take a little.Or you have to run multi-pass, maybe with some weaving on the cover/cap pass.And again as David reminded us, the usual size for a fillet weld bead is the same size as the base material.  So for 1/4 inch plate, you generally want the weld bead to be 1/4 inch up and 1/4 inch out and to NOT be concave (you do not want the weld bead to dip down, you want it to slightly curve up and be 'proud' of the area).And about the "heat rises" thing.  Sort of, but usually not fast enough to make much difference compared to the heat of the arc itself melting the steel.Looking closer at your pics, now that David mentioned the bead size, I think your beads and amps were on the low side of things.
Reply:Originally Posted by MoonRiseOh, and as David mentioned, single pass welds for steel rule of thumb is 1 amp per 0.001 inch thick.So for 1/4 inch thick steel pieces, you need 250A of juice.  Give or take a little.Or you have to run multi-pass, maybe with some weaving on the cover/cap pass.
Reply:Donald,what has torch type or size got to do with it? as long as the torch is operating within it's amperage rating it makes no differenceweld inspection is weld inspection. different processes may be associated with their 'own unique' flaws (e.g. tungsten inclusion) but a weld inspector is only interested in whether the weld meets the criteria.the TIG process does NOT produce concave welds- weldors do!
Reply:From the procedure handbook of welding By Lincoln electricNo one is saying you NEED 250 amps to weld 1/4", just for one pass welding that is a rule of thumb.  Just put a small bead on both sides of the T and try to break it.Last edited by David R; 01-14-2008 at 07:30 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Hi David,Are the drawing you posted also for TIG?  I have read on here a few times that TIG tends to leave a concave bead profile on fillet welds and that is usually what I always get even with the nicest looking welds unless I load up the filler instead of dipping the filler.Thanks!Build a Barstool Racer at BarFlyRacers.com!
Reply:Originally Posted by malich...I have read on here a few times that TIG tends to leave a concave bead profile on fillet welds and that is usually what I always get even with the nicest looking welds unless I load up the filler instead of dipping the filler.Thanks!
Reply:OK, I had some time today. This was a solid caster wheel mount.  I cut off the legs, flipped it over and removed all plating.One pass, the metal measured .210",  200 ampsbead profileTestedReal world weldin.  When I grow up I want to be a tig weldor.
Reply:This time I did 3 passes using a little less pedal3/32 red....Gas lenz Pure Argon, 1/8" filler.A good fillet needs no bevel for me.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:ONe more time. This one surprised me.6 passes, 250 amps, 1/8" cerated (orange)  1/8" filler.  Mill scale removed, no bevel.  The piece is about 2" wide 3/8.  Root bend.This was one pass 375 amps stuffing the filler in as much as I could.  I knew it wasn't near enough.That piece was 4" wide.  The weld broke right in the center. Yeah, I had some undercutting there.  DavidReal world weldin.  When I grow up I want to be a tig weldor.Hi David,Thanks for the photos.  They were kind of dark so I went ahead and brightened them up in photoshop and have attached them to my post.  Can you comment on them in the post order so I know what you were talking about?Thanks.Last edited by David R; 01-15-2008 at 08:49 PM.Build a Barstool Racer at BarFlyRacers.com!
Reply:David,On these passes, is the material 1/4" MS and how much pedal were you using in relation to the amps?  Maybe I should try the 1/8" Tung. as well.Thanks.Build a Barstool Racer at BarFlyRacers.com!
Reply:First set of pics, plate was .210.  Second set it was 3/8"  On the 3/8, I used all 250 amps each pass, only backing off towards the end.The only reason I use the 1/8 tungsten is I can see it better.  In the end I get a better weld because I don't contaminate it.  DavidReal world weldin.  When I grow up I want to be a tig weldor.