how to make a bigger TIG weld bead

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I'm at a point where my weldbeads look pretty good most of the time, however if I try to widen the bead out to make a little bit bigger weld the bead quality diminishes.Right now for the best looking welds I am moving the torch straight along in small steps, approximately 1/16" per step and then stopping very briefly as I dip the rod in the weld puddle. I watched Jody (weldingtipsand tricks) welding some aluminium with a similar style, it looked good enough for me,so I've copied that and had a good result.The weld bead with the filler rod I'm using is very small. I have two sizes of filler rod, .045 and .065. Both are being used on .065 tubing. The 065 does produce a larger bead but it is still a bit smaller than I would like for structural welds.For some extra strength it would be nice to build a bigger bead, but nothing so far has worked well for this. I've tried weaving , which works great when stick welding but didn't do it for TIG, and I've tried progressing with in a lower case e motion. The lower case e worked better than weaving, but still didn't make the nice consistent bead that a straight line step then pause motion does.Any help with this is greatly appreciated.Glen
Reply:Try 3/32 filler rod, you'll be adding more filler per dip than with the 1/16.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:I wonder, if you are getting the penetration that you want, with some positive reinforcement on the root and face sides, and you have complete fusion on both sides, then nothing is gained by making the weld wider, it would only make for a larger heat affected zone and more degradation of grain structure and properties.Are you needing to make the weld wider just to ensure good fusion?Any pics?
Reply:I'm still in the flat weld phase. My attempts at putting two pieces together weren't good so I went back to the easiest possible thing to practice on.I'm thinking that once I can consistently make good welds on the flat it will be time to try joining pieces again. This bead is 3/16" wide. Maybe that is OK? Attached Images
Reply:.065 is pretty thin.  as long as you're getting good penetration, the bead is as wide as it needs to be.  when you increase the thickness of the material, the bead will get wider.  I just did a project using all .065 square tubing, and butt joint beads looks like the one you posted.  I use .045 and .035 rod.  I tried to used 3/32 rod on .065 tubing, i just can't seem to get it to work too well on flat seams, it cools the puddle too much (my tig-fu isn't top notch, ymmv).  3/32 rod might work well on a fillet joint though.  larger rod might give you a wider bead, but wider bead means wider heat affected zone, which could cause more warping then you like.
Reply:Let the pool "wet-out" between dipping of the filler. If you rush in with filler and rush the travel, you will get "tall" narrow beads."SOUTHPAW" A wise person learns from another persons mistakes;A smart person learns from their own mistakes;But, a stupid person.............never learns.
Reply:I'll try all of the suggestions and post some photos of the results.I'm running out of SS crops again, might switch to mild steel. I find it easier to make a nice bead on the SS. Maybe practising on mild steel would be good though, get it down pat and the SS should be easy.
Reply:Could you get a shot from the end of your weld so we can see how much build up you have? It just looks a little tall, but it's impossible to tell from this angle.
Reply:I guess I welded right over that bead. Here is the plate I was practising on yesterday. As you can see, consistency is a ways off. Attached Images
Reply:Just remember that practicing on surface welds can only take you so far as a surfacing weld follows different rules for what is acceptable for weld appearance. The basics of TIG are simple make a puddle then dip move over make a puddle and dip. With that said, what size filler wire to use and heat to use and size of tungsten to use are all very interpretive for many people who aren't in an industry setting that follows a particular WPS (welding proceedure specification). I like to use the smallest tungsten I can for the heat I am putting down and a small enough filler wire that I can add more if needed rather that just dip it and because of its larger diameter adds in too much. So I know I didn't give you any specific instructions for tungsten size or amperage the intent was to give you the general idead of TIG welding theory. Hope it helps."I believe that our heavenly father invented man because his was disappointed with the monkey." -Samuel Clemens
Reply:I appreciate what you are saying, Mr. F.When I started tig welding a couple of months ago, I  used a Lincoln slide calculator that gives amperage, cup size, electrode, gas flow etc for any given weld type and thickness.I was told by the owner of the Lincoln welder that I was borrowing that the slide rule is the bible, don't stray from the recommended settings.It showed an amperage requirement of 70amps  for  an .065 SS fillet weld. I used that number and proceeded to make many, many overheated looking fillet welds in 065 SS. Finally one day a young fellow, who is in the middle of a three year welding program, dropped by. I asked him to give me some help with my tig welding practice.He started with the same heat setting I had but found it way too hot. After playing with the amperage some he settled on 48 amps as the right max pedal setting for  this weld and backed the pedal of some as the weld progressed. At that setting he made some really nice tig welds ,the final product being a silver/straw colour, not charred black like mine.So the first piece of info I was given, that the calulators are the gospel, was wrong!  They do get you in the ballpark, however trying to weld at 70 amps when 40 or 45 is what is needed can really through you off your game.Last edited by worntorn; 04-30-2010 at 10:39 AM.
Reply:On stainless you know you have hit the sweet spot as far as heat and travelspeed go when there is little to no sugaring on the back and your weld is multicolored like copper and blue when your done."I believe that our heavenly father invented man because his was disappointed with the monkey." -Samuel Clemens
Reply:Originally Posted by worntornI appreciate what you are saying, Mr. F.When I started tig welding a couple of months ago, I  used a Lincoln slide calculator that gives amperage, cup size, electrode, gas flow etc for any given weld type and thickness.I was told by the owner of the Lincoln welder that I was borrowing that the slide rule is the bible, don't stray from the recommended settings.It showed an amperage requirement of 70amps  for  an .065 SS fillet weld. I used that number and proceeded to make many, many overheated looking fillet welds in 065 SS. Finally one day a young fellow, who is in the middle of a three year welding program, dropped by. I asked him to give me some help with my tig welding practice.He started with the same heat setting I had but found it way too hot. After playing with the amperage some he settled on 48 amps as the right max pedal setting for  this weld and backed the pedal of some as the weld progressed. At that setting he made some really nice tig welds ,the final product being a silver/straw colour, not charred black like mine.So the first piece of info I was given, that the calulators are the gospel, was wrong!  They do get you in the ballpark, however trying to weld at 70 amps when 40 or 45 is what is needed can really through you off your game.
Reply:I know that now, but at the time I was quite impressed by the owner of the welder, Steve. He has a beautiful hotrod shop with about 5 or six customers' cars in there undergoing resto work. He showed me a Mustang clip which he had TIG welded onto the existing frame of a '39 Chev. convertible. The tig welds were as nice as I have seen. Some were done vertically and they were as nice as those done horizontally, though a little different in appearance.I did notice a small area on one side that wasn't quite as neat as the rest of the welding.Steve saw me looking at the rough spot and quickly told me that his nephew, David (the fellow in the welding apprenticeship) had welded that side. That explained the tiny rough spot and kept the premise alive that Steve's work was always perfect. I should also point out that when Steve first showed me his welder I asked him to give me demo and tips so I could get started correctly. He got the puddle started as I watched,  dipped the rod a couple of times then stopped and in a satisfied way said "There, that's what I wanted!".His Tig weld demo bead was about 1/8" long!A couple of weeks later I had breakfast with David and was quizzing him on TIG techniques. He may be just an apprentice, but believe me this kid can weld! He has spent the last couple of years doing mig and tig in the construction of housings for large gensets, working 8hrs a day and five days a week welding, other than periods spent in school. In his spare time he welds for fun!I mentioned the nice job he and Steve had done on tig welding the new clip to the 39 Chev frame. David looked really puzzled and said, "No we didn't do that, it was sent out to G&H Chassis  for the clip installation, they did all of that welding"Interesting the length some guys will go to in order to maintain the image of top dog.
Reply:heh,that's a funny story. thanks for sharing!if anyone was unwilling to work, neither should that one eat - 2 Thessalonians 3:10
Reply:You could always do a first pass..Then go over it with a "Stitch" or "Weave" pass over it..Don't matter if the parts are round or flat..These welds were all done with 1/16" 70S-2.....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:Can't be real, must be some kind of trick photography!You obviously don't understand that Tig welds are supposed to look more like the scabby things I posted above.Glen
Reply:Not a welding post, just trying to boost my confidence back up to somewhere above zero after looking at Zapster's  beautiful tig welding.here is a home my brother and I built some years ago.http://www.pixilink.com/tours5/1401-kerfoot-j/I spent about a month building the staircase in my shop then another week on the install.It's all built out of solid Honduras Mahogany . The stringers are made of out laminations I sliced up on our big bandsaw then welded together in the curve with glue and many clamps!The stair treads are hand morticed tightly onto the stringers (each one is a push fit curved mortice) to keep the entire stair rigid laterally.Honestly , when you see beautiful tig welding like Zapster does, you wonder whether just give up or forge ahead.Then I remember starting out in woodwork back in the 70s, the thought then of building a home or a staircase like this one would have been out of the question!I guess it's the same in any trade, you can learn enough to do a crude job in short order, but to turn out high grade stuff it takes years of learning and practising the craft.
Reply:Originally Posted by worntorn you wonder whether just give up or forge ahead. but to turn out high grade stuff it takes years of learning and practising the craft.
Reply:No worries, I'm not about to give up! Here is a practice weld made tonight on the small tubing which will make up the rear part of the frame. I think this will be the most difficult weld on the project because it changes from a fillet to a sort of lap weld then back again and it is all pretty tiny.This is 7/8" od .065 wall 304 SS1/16" red tungsten, .045 309L filler, 12cfh gas, 40amps+- Glen Attached Images
Reply:Looks good from here..Those are some of the toughest to do......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.