TIG like PIG

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Seemed like an appropriate title, guess you have to start somewhere. I was going to practice a little more before I posted anything for comments, but decided that correctly interpreting a weld is an important part of the process of learning. So, here are a few practice welds with some thoughts and questions. I used the following;1/16 inch mild steel 1/16 inch welding rod3/32 inch orange tungsten45 amps (47 on 1st weld)Miller Diversion 180 @ 110The 1st image is the top, the 2nd one is the bottom of the coupon. The 1st weld seemed a little too "hot", so I reduced the amperage from 47 to 45. The 2nd bead was less smooth from a travel perspective. On the 3rd weld, I slowed things down to see if that was better or worse. On the 4th I picked the speed back up again. I did try to let off the pedal slowly at the end, but still ended up with a pit.It would seem that the 1st bead, while not great, was the best of the 4. The slow travel bead (3rd) was the worst. For the 1st 3 welds, I moved the torch consistently forward and dabbed the rod in the puddle that seemed to be almost directly below the tungsten. On the 4th weld, I backed off a bit before dabbing the rod in the puddle. That seemed to give me a little better view of what was going on. Is that a bad thing to do/get used to?Any feedback/guidance is welcome! Attached ImagesLast edited by JoMo; 11-08-2010 at 11:13 PM.
Reply:You need to grind the surface clean first, and you're getting it way too hot.  If I had to guess, you're staying in one place too long because you're using too big a filler metal.  You're going to want no bigger than an .045 wire for that.  Try running some beads without filler, first.
Reply:What he said +If you are just starting out a single coupon and 16ga. material it will be difficult to control your heat. The coupon itself will be hot enough after one weld to change your heat / travel speed making it difficult to learn a repeatable pattern.Try thicker material with multiple coupons. Make a weld on one coupon, move it aside to start cooling while you weld on the others in sequence. Unless you have quite a few you may need to let them cool some more before you start over. Ken
Reply:what they said +scratch a line on the coupons (maybe in the middle) so that you have something to go by in order to keep the weld straight. Once you have the first bead laid down straight over the line it should be fairly easy to lay a bead right up tight to the first bead and so on.Someone here gave me this same advice 6 months ago and it really helped .
Reply:My first Tig welds with my Diversion 165 looked just about like that - maybe worse.  1 year later I can lay down some pretty nice welds in both steel and aluminum.  I had to take a class, then go through about 4 tanks of shielding gas to get there. Here's what I would say you are doing wrong: 1. The material isn't clean enough.  2. I'm betting you've contaminated the tungsten - break off the contamination and resharpen.  3. What size filler rod are you using?  Looks too big, which cools the weld and forms blobs.   4. You're holding the torch way too high.   1/8 inch from the puddle is where it should be - which will cause you to dip the tungsten in the steel - see #2.   5. Do you have a good ground? - the diversion needs a good ground 6. Is your gas flow at 15? and is your torch stickout about 1/4 inch?.After I learned all those setup things, and I still couldn't get consistently good welds.  I had a problem with my auto dark helmet - it was flashing on me and I couldn't see the puddle well enough - I was simply watching the flash of the arc and sticking the rod in there.  With Tig, it's imperative that you see the puddle form across the two pieces of metal, then see the puddle advance when you move the torch.  If you can't see that level of detail, you need a different helmet.  I ended up with a non auto helmet that seemed to work best for me.
Reply:Ok, thanks everyone, that's a lot of great feedback. Here is a summary of what I heard and what I will try:1. Clean - I started with a clean blank thinking that was Ok. I will try (lightly) grinding the area 1st.2. Too hot/Filler rod diameter/Too thin - I will switch to 1/8 inch (multiple) coupons and post my new settings for that, since it sounds like that is an easier place to start.3. Travel - I will score a line. I tried to use soap stone, but that didn't really work well. 4. Tungsten - I keep it sharpened, but haven't cut it. I suspect this is part of the issue, it isn't totally smooth on the sides.5. Height - Will keep working on this. I can see the puddle, but when it is hot, the tip looks "rounded" to me, so it is hard to gauge distance. Maybe this is due to using to much amperage. Will report back.6. Other settings - good ground - yes; gas flow 15 - yes; 1/4 inch stickout - yesSince no one said it is normal, I will assume that I should never back off the torch for better puddle visibility. I guess that would probably impact the already "welded" area in any case.Last edited by JoMo; 11-10-2010 at 08:58 AM.
Reply:I missed that you had 1/16 rod - that's thin - I think I normally use 3/32.Yeah any steel has oxidation - unless it has just recently been cut - so it will need a hit with a grinder before you weld.  Don't cut the tungsten - just clamp the tip of it in a vise and snap it off, then regrind the end.  For the Diversion I've had best luck with a sharp pointed tungsten.  It shouldn't look rounded in the arc - it should still look pointed, and that allows you to direct the heat.  If it's rounded, you probably touched it and burned the end off - in which case you cannot weld anymore.  I usually sharpened 3 tungstens at a time while I was learning, and sometimes used all three in 10 minutes or so.  Make sure you have a good base for your torch hand - you can't freehand a Tig torch (well, I'm sure really good welders can, but I can't.)  1/8 of an inch is really close to the puddle, but that's where the tip needs to be - it'll take awhile to learn to keep it there without dipping it into the puddle.  Also are you holding the torch nearly vertical?  That's another thing I was doing wrong at first.  It needs to be no more than  just a few degrees off vertical - and the filler comes in almost parallel to the workpiece.   Keep at it.  Tig is almost magical when everything is going right, and frustrating when they go wrong.
Reply:Got to say I think a slight push on the torch angle is better than 90 degreesG
Reply:Ok, I had read the 1/16 was the normal thin. Either way, I moved up to 1/8 inch coupons - I think that 1/16 is still the correct filler.I was wondering about sharp, or with a slight grind off of the point. I am using sharp, so that sounds right. I noticed that setup (positioning) is huge for me. I actually switched the pedal to my left foot because that allows me to use my right hand more easily. I am using the (makeshift) table as a guide for my palm. It is hard to believe that I will be able to translate such a controlled environment to the field, but I am sure that is easier over time.I am tilting the torch slightly to the right and feeding the rod with much more angle than the torch. I can see the point now.I am posting round 2. I think that your suggestions made a noticeable difference. Still not great, but progress! The 1st 3 are at 90 amps without filler rod. The 4th is at 90 amps with filler. I thought that was too hot, so I went to 85 amps for the last 3. I think that 5 might be the best. On 6, I touched the tungsten and had to grind/restart in the middle. I only had one coupon, so 90 might be correct if I wasn't welding multiple times.Again, any feedback is welcome. Although I must admit, I didn't expect everyone to be so nice about it!I am using an orange tungsten. Any thoughts on the difference that using red or blue would make? Attached ImagesLast edited by JoMo; 11-10-2010 at 10:36 PM.
Reply:Looking better already huh.You have received a lot of good advise.Stick to the 1/16 filler rod for now, you don't have any root that you are trying to fill and anything larger may cool your puddle to fast while learning. I think you will learn better peddle control this way.At the end of the weld you may want to double dip the filler to help eliminate the hot crater you have going on there, as well as starting to release the peddle sooner but slowly and give  a slight swirl as not to leave either a hole or nipple.Practice, practice, practice.Ken
Reply:try jamming those beads tight together, you might find it easier to keep things straight if you keep the edge of the cold bead right at the egde of the puddle for the new bead as you go. It is good  to learn to keep the beads straight although it might seem that it shouldn't matter right now.I guess it is just one more motor skill you are learning as you go- that of putting the weld bead exactly where you want it rather than in a random place.Big improvement already!
Reply:Looking better. Your on your way!!!Ya gotta spend money to make money!
Reply:Those are much better and the last 3 are starting to look good.  It'll be harder again as soon as you try to weld two pieces together, but you're starting to get the hang of it. After awhile I just started running beads on top of beads during practice - I was more worried about developing the hand skills than I was being straight or getting good penetration.  A few more things that helped me: 1. I bought a Stronghand Nomad folding welding table - awesome little device - after burning off the wooden top of my workmate.     2. I got the next sized smaller tungstens - I bought pure tungsten (don't like) and Thoriated (works about the same as the orange) - I'll probably just stick with the Orange ones in the future.  3. Despite what all the online videos said, and the instructor told me, I make my best welds when I advance the torch at a very slow steady rate (vs. step movements), while confirming that the puddle is advancing with it.  I then dip the filler quickly and at very short intervals.  When you weld two pieces together, don't forget to tack both ends before you start the bead, so the gap remains steady.
Reply:Pure tungsten is not made for DC welding.There is a considerable amount of porosity.  The type of porosity being shown, particularly the little "volcanoes" where you terminate your arc, is characteristic of base metal that isn't clean.  You need to do more than lightly grind.  You should be looking at bright, shiny base metal, not just polished mill scale. What size gas cup are you using?
Reply:Hey quick question, sorry if its off topic. Have you had any problems with high frequency interference with this unit? Are you welding in your garage? Thanks!ShaneYa gotta spend money to make money!
Reply:I weld in my garage, and I'm not sure if I've had any interference, but I haven't noticed anything.
Reply:Ok, some more good ideas. Will include working on:1. Running the beads right next to each other2. Using a grinder vs. belt sander - the metal wasn't totally flat and there were a few small areas that were not as clean as I wantedIndyWelder - I like the Nomad table, I am going to add it on my list after the plasma cutterSupe - I am using a 7 gas cupShane - I am welding in the garage and haven't noticed anything. I usually listen to a radio and it is clean, but I am sure that I don't hear it while I am actually welding. No reports from inside either.
Reply:As I continue to work on my practice welds, it seems that I get much more control if I drop the amperage to 77 (from 85) for 1/8th inch mild steel. Things seem to go much slower and I can see them unfolding better.Any thoughts on 77 being enough? My welders chart indicates 75 is the min and 130 is the max, so it would seem to be on the low end.Also, anyone interested in posting a sample weld picture for me to use as a target? Something that I should be able to accomplish in my 1st few months on mild steel, not a medical quality exotic metal weld!
Reply:Green tungsten not used with an inverter. A/C alum transformer mostly.V.
Reply:Attached is one of my 1st attempts to join two pieces (1/8th inch), along with some questions:1. What is the trick to avoid the indentions on the ends? More filler, less heat and a lot more practice?2. From the front, I might say it was too hot. From the back, not hot enough. Thoughts? Do folks usually weld both sides?3. The place where it is "extra" wide is where I tacked it. Any help on how to perform a good tack? Do you use filler for your tacks?4. I was having to re-sharpen my tungstens after every few inches while practicing. I backed off a little and that seemed to do the trick. I guess that I was actually too close to the puddle, but didn't think that was possible. Does that seem like a reasonable assessment? How long should I expect to go between sharpening when I have more experience?It is like starting all over!Thanks Attached Images
Reply:The indentations on the ends is where the puddle got too large and surface tension drew material into the puddle.  Use less heat when the puddle is near an edge like that.  For now I wouldn't worry about getting full penetration.  Work on consistency first.  For full pen on plates like that I would bevel the edges at 30-45° (30° from vertical) and tack with ~ 1/16" gap (I like the root opening to match filler rod size).  I'd start about 40-50 amps and see how that works, wait for the joint to keyhole before adding filler.  The goal is a uniform root appearance, with no whiskers (unmelted wire) and less than 1/16" reinforcement.  Make tacks as small as possible.  I almost always use filler for tacks.  Get a small puddle going on each side of the joint, then dab the filler directly between the two puddles.  The filler should draw into each and evenly bridge.  When making small welds and anything for RT inspection I weld between tacks, then go back and cut the tack out and feather the starts and stops of the sections I welded.  Otherwise, when welding add less filler at the tack.Each time you add filler the puddle gets a little taller, move forward and it gets farther away.  There is not problem with backing the torch away slightly each time you add filler, just so long as you maintain proper shielding gas coverage.  As you get better, you will contaminate the tungsten less often.  Eventually you will start getting to the point where you sharpen because the point has eroded away enough that the arc starts spreading out or wandering.  A tip for beginners, don't worry so much about re grinding after every time you touch the tungsten.  If the arc is still focused, and there isn't a big blob on the tungsten just keep going when you're practicing.  Resharpen when the point melts off into the puddle or you've got a large blob on the tungsten.  Just for practicing.  There's not much point in spending more time at the grinder than hood down.  When welding for a customer, or yourself, regrind a contaminated tungsten.  Try adding filler more frequently. Add less filler each time.  Less filler, more often.  #6 is my goto cup size.  I prefer collet bodies to gas lenses most of the time.  I use a #20 torch, been several years since I've touched a #17/18.  I'd guess I hold the torch at about 60° from horizontal in most cases.
Reply:Thanks for the information Static-XJ. I am experimenting with the pedal, so hopefully that will help with heat control. I tried a bead with the amps set way down and for the 1st time I was happy with the consistency/control. The bead was too cold, but other than that, it looked great (for me) and the tungsten lasted for at least 15-20 minutes of welding. I was able to add filler more frequently as well, since I wasn't forced to keep moving so quickly. I was thinking about setting the amps up, but using the pedal for more control over the entire weld. Do you use the pedal continually while you are welding, or just at the start/finish? As soon as I get a little better "control", I will give the beveling and tacking a try.I will get a #6 and try it out. I don't think that my torch uses either of those (collet/lens), would you recommend one? The Diversion 180 is limited on torches. I have the 17lgc, but can get the 9lgc for a reasonable price. I assume the #20 is smaller, correct? I think the 9lgc is smaller, so if smaller is easier, I might want to give that a try.
Reply:Here is an example on 1/8th using 65 amps. It's too cold, but things feel Ok with those settings, so I am going to keep working on bringing the amps up to where they should be. Attached ImagesLast edited by JoMo; 11-21-2010 at 09:59 PM.Reason: Attaching a more realistic size image
Reply:Originally Posted by JoMoI will get a #6 and try it out. I don't think that my torch uses either of those (collet/lens), would you recommend one? The Diversion 180 is limited on torches. I have the 17lgc, but can get the 9lgc for a reasonable price. I assume the #20 is smaller, correct? I think the 9lgc is smaller, so if smaller is easier, I might want to give that a try.
Reply:Originally Posted by JoMo I was thinking about setting the amps up, but using the pedal for more control over the entire weld. Do you use the pedal continually while you are welding, or just at the start/finish?Top is the standard collet collet body and #8 cup for my WP17. Below is the gas lens and same size #8 cup. Note cup on top is turned around backwards for some reason when I took the picts a while back. Attached Images.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 DSW/Static-XJ, I do plan on trying aluminum in the future. I took mine apart as well and do see the collet body now. Will continue as is (#17 and collet body, may try #6 cup) and when I get a little better experiment some other options. It looks like collet body and pyrex cup is also an option to try.Static-XJ, that is helpful on pedal use. I can tell it is going to take a while to get that one down. At least I will be practicing with the proper target in mind.
Reply:Ok, after a short side track to get a plasma cutter setup to cut coupons, I am back at it. I have been using Tom Bridigum's book "How to Weld" as a reference and plan on working through all of the different welds in it as a start. Below is one of my attempts at exercise 1, "autogenous weld". I have been able to make the start and finish look better by using better control of the pedal, other than that, this is what they have been turning out like. Any feedback (other than give up!), is welcome.Thanks,Joe Attached Images
Reply:Originally Posted by JoMoOk, after a short side track to get a plasma cutter setup to cut coupons, I am back at it. I have been using Tom Bridigum's book "How to Weld" as a reference and plan on working through all of the different welds in it as a start. Below is one of my attempts at exercise 1, "autogenous weld". I have been able to make the start and finish look better by using better control of the pedal, other than that, this is what they have been turning out like. Any feedback (other than give up!), is welcome.Thanks,Joe
Reply:Thanks Dave, I will keep that in mind when I get to Aluminum.