Questions from Tig newbie

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I've been playing around with tig welding for the first time ever.  I've read lots of articles and watched tons of videos but it definitely seems to have a big learning curve.  I'm using lift start tig, a 17 torch with 100% argon.  I've been practicing on .060" mild steel at around 60amps and argon flow set to 15cfh.  I purchased 1/8"  er70s-02 filler rods but I think I should've bought 3/32" filler instead.  I'm using 3/32" 2% thoriated tungstens.  Right now I'm just practicing pushing the puddle across the metal without filler.  I'm using a #5 cup and I'm wondering if that's the right size?  I've heard about gas lenses and I'm wondering if that's something I should purchase in order to decrease my argon consumption.Any tips that may help me out a bit?  Do filler rod sizes correspond to specific amperage?  What size is recommedned for 60a?  At what amperage should I be able to successfully use the 1/8" rod?
Reply:when it comes to tig, truly there are alot of variables, from temp, humidity, input power quality. the answer is, what works for you. you need to learn your powersource, on .060 with 3/32 you will find yourself running higher amperage than if you are welding with 1/16 tungsten. puddle size/shape directly relates to how you weld, and tungsten tip shape. Filler rod is as needed. you can weld with 3/32 or 1/8, you will find one works better than the other for any given situation.The biggest mistake people make is going too fast, and not letting a good uniform puddle develop and remain.  Don't rush. Just mess around and try different things, you will find what works for you. Tig welding is kind of like a golf swing. the symantics are different for everyone. the important aspects are mantaining a good puddle,  and taking your time.Your settings are a great ballpark baseline. I will tell you my shop is at 1200ft elevation, my house is at 4250ft elevation. I can tell you there is a BIG diffence between welding @ home, and at my shop.Last edited by sausage450r; 03-15-2014 at 05:50 PM.'14 HTP invertig 221Thermal Arc 201ts'15 HTP 2400'13 Hypertherm Powermax 30Esab 875Esab 251Clark Metal Servicespecializing in stainless steel exhaust systems
Reply:Fillers you are looking at are MUCH larger than your base material. Remember you melt the filler with the PUDDLE, not the arc. That makes it very hard to use large filler and not blow holes in things. .045 filler may be a better choice. They sell it as rods, or you can use mig wire if need be..060 material is smaller than I'd recommend someone for learning unless you really want to learn super thin tig. Heat control will be difficult, especially if you don't have a pedal with really thin material. 14 ga would be better, 1/8" is what the school uses. With 1/8" material we use 3/32" rods.As far as the gas lens, they are nice, but not required. On thin stuff like you are using, a #5 may be fine. School uses #7's with steel, #8 with alum. Day instructor is old school, so the only gas lenses he uses is for when kids get to pipe and start walking the cup. I like to use gas lenses with students because it allows them to extend the tungsten a bit farther without having gas issues. This allows them to see the tungsten a bit easier and helps prevent them from dipping the  tungsten. The ability to slightly lower the gas flow isn't bad either. Biggest gain I find is that they don't dip the tungsten as often, so don't get frustrated by spending all day grinding.I've done several "how to tig" threads. Take a look at  one of them and see if they help. If you can't find one, let me know and I'll hunt up the link..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Thanks for the tips.  I've continued to practice running beads without adding filler.  Attached is a butt joint that I ran without filler.  This was at 60amp and as you can see I burned through at the end.  I also took some mig wire, folded it over and spun it with a drill to make some ghetto filler.  I had trouble with puddle control.  I quickly realized the puddle was what melted the filler.  My biggest issue was that I think I was moving too fast.  I think I was out-pacing the puddle because I was blowing through the metal.  I decreased to 50 amps and I think it helped.  It allowed me to slow down and direct the puddle.  At that point my problem moved to my filler hand which seemed to have a mind of its own.  I felt like I had no coordination or rhythm.  This will take a lot of practice! Also, my beads sometimes appeared flat and kind of dull looking.  What would cause this?  Not enough shielding?  Too fast? Attached Images
Reply:All that nice red around the bead says you either dipped the tungsten in the puddle, or you fouled it with filler. You need to stop and regrind the tungsten as well as reclean your material. Also thin material can allow you to pull contaminants like scale from the back of the piece. If the puddle goes all the way thru ( and it's easy to do with thin material) some of the "dull" bead can come from this.Other things that can cause a dull bead is moving too slow. You heat up the material surrounding the bead, and after you pass it can't cool down enough before you loose shielding coverage. Poor shielding can cause this also, but usually that shows up more as porosity. The dullness is a thin layer of scale starting to form many times.Tig can be a lot like patting your head and rubbing your belly at the same time. Your hands usually want to work together. If you dip filler with your left, your right hand almost automatically wants to mimic the same motions until you break this habit.  With newer guys I like to teach them to use the lay wire method, or "slide" the filler along the piece into the puddle. With the lay wire, you start the puddle then bring the puddle to the filler so the puddle melts the filler not the arc. You may have to keep advancing the filler as needed. When you slide the filler it's very similar to lay wire when you advance the rod. Next thing is to "tap" the filler in like using a drum stick. Since the hand doesn't move much, it's less likely to effect the torch hand. I move guys on to this after they get a bit more experience.You have a lot of things that all have to be controlled at once with tig. Try and cut all the variables from the equation possible so you can work on one at a time to start. Then add one or two together as your skills improve. Keep thins simple now and it will be easier..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by DSWAll that nice red around the bead says you either dipped the tungsten in the puddle, or you fouled it with filler. You need to stop and regrind the tungsten as well as reclean your material. Also thin material can allow you to pull contaminants like scale from the back of the piece. If the puddle goes all the way thru ( and it's easy to do with thin material) some of the "dull" bead can come from this.Other things that can cause a dull bead is moving too slow. You heat up the material surrounding the bead, and after you pass it can't cool down enough before you loose shielding coverage. Poor shielding can cause this also, but usually that shows up more as porosity. The dullness is a thin layer of scale starting to form many times.Tig can be a lot like patting your head and rubbing your belly at the same time. Your hands usually want to work together. If you dip filler with your left, your right hand almost automatically wants to mimic the same motions until you break this habit.  With newer guys I like to teach them to use the lay wire method, or "slide" the filler along the piece into the puddle. With the lay wire, you start the puddle then bring the puddle to the filler so the puddle melts the filler not the arc. You may have to keep advancing the filler as needed. When you slide the filler it's very similar to lay wire when you advance the rod. Next thing is to "tap" the filler in like using a drum stick. Since the hand doesn't move much, it's less likely to effect the torch hand. I move guys on to this after they get a bit more experience.You have a lot of things that all have to be controlled at once with tig. Try and cut all the variables from the equation possible so you can work on one at a time to start. Then add one or two together as your skills improve. Keep thins simple now and it will be easier.
Reply:You shouldn't be pulling rust off the beam. I see back contamination a lot when guys do a lot of welding on the same piece and don't keep it clean. Beads suck the scale in from the back when you are talking thin material where you can get the back  molten as well as the front.As soon as you dip, STOP, and regrind. If you wait until the arc degrades, it's really fouled and it's a bad habit to get into. Get used to grinding, you'll do it  a lot..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by DSWYou shouldn't be pulling rust off the beam. I see back contamination a lot when guys do a lot of welding on the same piece and don't keep it clean. Beads suck the scale in from the back when you are talking thin material where you can get the back  molten as well as the front.As soon as you dip, STOP, and regrind. If you wait until the arc degrades, it's really fouled and it's a bad habit to get into. Get used to grinding, you'll do it  a lot.
Reply:Acetone works well because it gets rid of oils and grease that doesn't come off easily. Some guys use denatured alcohol vs acetone. Chlorinated break cleaner should be avoided at all costs unless you know for sure they will have time to dry completely, say you are cleaning the day before and there's no nooks and crannies that could hold the cleaner.I use Acetone, most of the time myself, but at the tech school, we don't have that available for fire safety reasons ( plus I'm sure they don't want the kids snorting the fumes ). The guys just have to grind and wipe things down dry, but we do use clean new steel. Occasionally we get  really oily steel in and then we have a few issues and need to deal with it. Soap and water if nothing else is available, gets the worst off..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:At this stage you should swap for a clean tungsten every time you even suspect contamination. Try to get contact between the back of the coupon and some thick aluminum, then try to get the HAZ lines straight, good luck and get some .045" filler and clean metalSqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A
Reply:So I decide to build a welding cart and the steel yard only has 1" square tubing in 16 gauge when I was planning on using 11 gauge.  Thought the 1/8" would be better for rig practice.  Needless to say I bought some 16 gauge and started cutting and assembling the cart.  I used 55A setting with 3/32" filler rod.  I had reasonable success tig welding the mitered corner joint (3 side, top, bottom, and inside corner).  I didn't attempt welding the outside corners.  Going to practice on some scrap before tackling the outside joint.  The one area I had the most problems with was welding the cross braces in place.  Its basically a butt weld but I had problems with amperage and puddle control.  Seemed like I kept blowing out the end of the brace when it meets the tubing at a 90 degree angle.  If I set the amperage for the middle of the tubing it was too hot for the end of the cross member.  And vice versa.  I ended up using the higher amp setting and focusing the arc primarily on the tubing and would quickly move the puddle toward the brace while packing filler rod.  Its the only way I could get a reasonable bead.  Since the cart is not all that structurally important I guess its good practice.  But I almost pulled out the small diameter 6013 and tried stick welding it.  I'm only about half done but I think Ill just tig weld the entire thing.  Will give me some good practice.
Reply:16 ga tube and 3/32" filler will be some what of a challenge. 16ga is roughly 1/16", so your filler is 50% bigger than the base material. That makes it really hard to get the puddle hot enough to melt the filler. My guess is you are melting the filer with the arc, not the puddle. No good. 1/16" filler is a closer match to 16 ga, but being the same size as the base material, it may still give you issues, especially since 16 ga is a bit on the thin side for guys just learning. .045 filler is a much better match, but no all places stock it. .035 mig solid mig wire can be used, And some guys double it up and twist it in a drill to create a bigger filler rod for use. You may find smaller filler will help with your heat issues.One "trick", is to start on the outside, and work in, if need be meeting in the center. You should learn to weld to an edge, but when new, without as much skill, this can allow you a bit more control.If I'm remembering correct, you are doing scratch start without a pedal, so you will be limited in your heat control options. One big thing that I see quite often. New guys love to angle the torch a lot so they can see the puddle and tungsten easier. This washes a lot of heat out front and preheats the area in front of the bead. Keep the torch at almost 90 deg straight up and down, ( slight tip say 5 or 10 deg max) and you pump that heat down, not out and you may have more control near the edges..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Thanks.  I stopped by my LWS today and picked up some 1/16th filler.  It was the smallest they had.  I've tried the mig wire trick and it worked but it tended to melt before the filler hit the puddle.  So maybe 1/16th will be my sweet spot.I'm using lift start tig with an SR17 torch.  I don't have any issues initiating an arc.  That part is very easy.  The biggest problem with the lift start is pulling off.  I try to pull off fast and immediately get the torch back in position to allow the argon to cool the bead.
Reply:What brand tig did you buy?
Reply:Originally Posted by blackwaterstout  I've tried the mig wire trick and it worked but it tended to melt before the filler hit the puddle.
Reply:Originally Posted by mliebsWhat brand tig did you buy?
Reply:Originally Posted by DSWI'm betting your issue with mig wire at those amps is due to torch angle as I mentioned in the last post.
Reply:Work is continuing on my mig cart.  I'm starting to get the hang of it and the beads are looking a lot better.  I'm using both 1/16" and 3/32" filler rods and about 63 amps.   This is giving me lots of good seat time.  Ran a lot of beads and only contaminated 1 tungsten today!  Now I want to go back and clean up some of the earlier crappy welds.  Most notably the 3 joints that I blew substantial holes in.  I'm wondering what the best way is to fill these holes.  Should I decrease my amperage and use smaller filler in order to cut down on the amount of heat?  What's the correct procedure?
Reply:This is where I'd use the larger filler. I'd use the filler rod as a "plug" to fill the hole and use the arc to fuse the filler to the material in the hole. If the hole is really big, you might have to do this 2 or 3 times until you bridge the gap. Small things you can come back and fill later with smaller filler if need be once you close up the big holes..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:If your holes are due to porosity you will never fill them in, they'll just keep bubbling. A quick hit with the drill can help clean that up so you can fill it, a dab of stainless fill can also smooth things out. 3/32" filler should have at least 100 amps, I'd rather use 1/16" at 140A than 3/32" at 60A.SqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A