Critique 1G butt weld

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I'm well behind in class.  About 4 projects.  Here is the next one, I've been practicing at home.  It's a 1G butt weld.  I just can't get a handle on the puddle.  We're on spring break so the instructor isn't available.  Plus I'd like to get a different perspective from the pros here.  There is not a formal process but there are parameters that are required on the machines at school.  Process DCEN GTAW.  I try to get a Dynasty 200DX when I can.  Mild steel, A36, 14 ga hot rolled.  100% argon at 20-25 cfh, 1/16" 2% thoriated or 1.5% lantanated. (I'm using lantahanated, GTP).  Root gap, 1/16", filler 1/16" ER70-S2, 65-100 amps, 5 sec post flow, #6 nozzle on a WP17.  My home rig, where these coupons came from is different, Square Wave 175.  It's a WP9 with a fixed post flow, got the dial at 80 amps and working the pedal.  Trying to read the puddle, I can see it but having a hard time controlling it.  I can do an inch or two at a time, I'm screwed on a 6 inch full coupon.  The back penetration is kicking my ***.Remaining are a 2F T on mild steel and the 1G butt and 2F T on stainless with 308L filler.  To start AL on time, I need to have all these complete, in the lab not at home in a 5 hr lab next Sat.2 is the top, 2R is the bottom.1g butt top 1 g butt bottomAny help, particularly from DSW or Sundown no matter how brutal is appreciated.Last edited by dstevens; 03-25-2012 at 04:49 AM.Reason: forgot to mention the process
Reply:Try keeping heat input more consistent. On 14ga try around 80ish amps and just keep the pedal floored, keep up with filler. From the pics it looks you are varying the pedal too much.Also tungsten selection is fine, argon may be too much. Shouldn't need more than 15 cfh for this app.
Reply:For hell's sake grind both sides of the joint before welding, man! That will help you immensely!  You may try grinding a small bevel on the edge of both plates before you tack them together.  this'll help with penetration.However, don't do this if they don't allow that sort of thing on the test coupon. Aside from that........... what you need to do you need to keep practicing. Looks like you're going too fast at the start, then you tried to compensate with too much current.
Reply:For hell's sake grind both sides of the joint before welding, man! That will help you immensely!  You may try grinding a small bevel on the edge of both plates before you tack them together.  this'll help with penetration.However, don't do this if they don't allow that sort of thing on the test coupon. Aside from that........... what you need to do you need to keep practicing. Looks like you're going too fast at the start, then you tried to compensate with too much current.
Reply:Dstevens, I could not agree more with joshfromsaltlake. A clean edge to work from will make a world of difference. To me prep is just as important as the weld itself, both done properly, the results are great. Lots of luck.
Reply:Here's what I see. I circled what I believe are the same areas front and back in the same colors since it looks like you flipped the image of the back 180 deg and it makes it a bit more difficult to understand for some.The red circled area is simply too cold. Your puddle is way too small and it clearly shows from the lack of penetration on the back side.The yellow circled areas are about what you are probably looking for. Whatever you are doing there, you simply need to continue. Often I find students who can make very nice short beads, but can't seem to do longer ones have issues with how they are positioning their bodies or hands. Where we are at, lots of times it's because the weld tables are very small and the mig/stick guys have  welded up all sorts of bumps and such by tacking straight to the table or burning off the wire on the table edge leaving a very rough and jagged surface. I always suggest students start the class by taking the table off the stand and grinding all the edges smooth so there is nothing to snag a glove or cuff on as they try to weld the bead. A 2nd option when the tables are super bad is to simply take a  piece of 1/8" coupon and tack it to the edge of the table to make a nice clean "shelf" they can slide their torch hand along as they make the weld. You should be able to make the whole move from side to side on the coupon with no changes to torch angle or arc length in one smooth continuous motion. Take advantage of natural rests. I see a lot of students trying to weld with their arms out straight in front of them. They seldom can hold the torch steady or move freely because they have their muscles locked. Sit, lean on the wall, rest your hands on the table, add a prop to raise your arms to the right level... whatever. The other week I welded up the alum box and I had my right arm propped up on a creeper that was leaning against the weld table to hold my torch arm up comfortably at the right height. You often see Zap has a bar or block to rest his hands on while doing possioner work. Support your weight with your bones not your muscles and you will be steadier.The 2nd issue students have with "short" welds is that they haven't learned to feed filler well over long distances. They can usually feed about 3-4" of filler rod, then they have to stop and "reload" to do the next few inches. I often suggest students keep the filler in direct contact with the plate and "slide" the filler into the puddle rather than try and "dip" ( it usually ends up more of a stab action) or try to "tap" the filler in like playing the drums. This allows them to hold the filler out farther and still keep good control of the end of the filler. I've never really gotten the roll and slide action with the filler and gloves with my left hand. I can do it bare handed, but I don't do that with students. I simply need to spend more time doing it on a regular basis.The blue circled are looks like you got it way too hot. Traveling too slow would be my 1st thought. Students often ask me how many amps I use or how much I push down the pedal on a certain weld. Most times my answer is "enough to get the puddle to look like I want". It's the truth, but not very satisfactory for most people. I need to really concentrate on just how far down I have my foot to really tell them the answer, and usually that takes away from the attention I need to do a nice weld. It's sort of like trying to explain how far down the accelerator pedal needs to go to drive 35 MPH. What you are driving and the road conditions means you are constantly making minute corrections without even thinking about it. Heat control is the same, except you get to throw arc length, travel speed and filler in the mix as well.Try and visualize exactly what the puddle in the yellow section looks like as you weld it. That's the look you are going for. Learn to ignore the arc and concentrate on the molten metal. I don't think you are quite there yet "seeing" the puddle. I'll admit some days my eyes don't see the puddle as well as they do on others, especially if I'm swapping from mig to tig to stick randomly in one class working with students. Try and limit the variables as much as possible. Keep you little finger of your torch hand on the table and hold the torch angled with the tungsten at the right arc length. You should be able to slide your hand back and forth smoothly without even looking at your torch and maintain the same arc length/travel speed. This will eliminate 2 variables ( arc length and travel speed) from the puddle equation. Then concentrate strictly on puddle control with the pedal. Also don't have a death grip on the torch. You want control, but you want to have the torch held in such a way that you can do it for 10 minutes and not get fatigued or even notice you are holding the torch. It's a lot like holding a pen of pencil. It should just rest in your hand.The suggestion on fine tuning your amps with the machine is a good one. I use it whenever I have a student that simply can not consistently maintain the right amps. It will take a bit to dial the amps in if you don't have someone who can do it for you. Keep in mind the closer you are to "optimum" amps on the machine, the better fine control you have over the heat. It's much easier to go between 75-85 amps with the peddle with the machine set at 90 than it is if the machine is set at 200. The down side is if you need 95 or 100 amps, you can't get it with the machine set at 90...Filler I'd suggest "sliding" the filler into the puddle rather than "stabbing" it. Guys with issues feeding filler I usually suggest using the lay wire technique until they manage to get the rest of the hand and foot motions down. It's like trying to pat your head and rub your stomach while hopping on one foot. It takes a bit of practice and usually someone ends up either patting both their head and stomach or rubbing both because the hands want to move the same way. Again the idea is to limit variables at this time. You want to add filler at a consistent rate and not take your attention away from watching the puddle. Just make sure you are melting the filler with the puddle, not the arc or this is pointless.Butt joints are usually the hardest to do. It's all about practice. Good luck. Attached ImagesLast edited by DSW; 03-25-2012 at 09:33 AM..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 guys.  Great stuff.  I'm on  my way out the door but will respond in more detail when I get the chance.  It's helping, thanks!Dave
Reply:Make sure you have a current eye exam. We reminded all students of this. Prescription should be for welding distance, which you must SHOW eye examiners because they aren't welders.I suggest cleaning a practice plate and run beads a minimum of SIX inches long. Short beads won't develop the fine muscle memory you need. Run and run and run and run for several hours. Straight beads, next to each other. We had everyone do beadds until they smoothed out.
Reply:Very true on the glasses. I have recently gotten a "new" prescription that's weaker than my normal set because I'm near sighted and used to frequently find myself looking over the top of my glasses to see better. It takes me a bit to adjust every time I put these new glasses on. Some times I still find I can't see the puddle as well as I'd like to, often because I get light in behind the hood and my eyes try to focus on the face of the lens rather than the weld. That or the fact I probably should have gotten the lenses set for a bit closer than the 18"-24" focal length the Doc suggested. It's perfect at arms length, but if I get in real close,  some times it takes a bit to adjust my eyes. I usually find I need to put the new glasses on for about half an hour to get my eyes to adjust to them before I need to do any detailed work like welding..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 guys, it help.  A couple of thoughts.  As far as 80 amps floored, it gets too hot and blow a hole right through the material.  Looking at the instuctors rig he gets a puddle at 80 then finishes at about 65 constant.  Stack of dimes.Glasses.  Blended tri focal with poly carbonite lenses but I can't wear them in that shop without additional eye protection.  I can't find the right cheater fo the Speedglas 9100x locally but have been looking online.  Heat is killing my torch hand.  I just got a TIllman 550 shield and that helps a bunch.  I'm headed out right now to cut another 50 coupons and got a some SS scrap given to me by the steel yard.  Need to get some 308L filler in the morning to use to practice.  To catch up to start AL I need to finish four more on Saturday.  1G butt in both SS and mild steel and 2F T in both metals.  I've asked to take the class as an audit but was declined. They don't do that.  It's vo-tech class.  I'm at a solid 85 right now, thanks to a strong mid-term and quizzes but the practical, as you can see, I suck.  It's frustrating but I'm going to keep at it.Thanks again, it all helps.
Reply:The trifocals may be part of your issue, I take it you are farsighted? They make  safety glasses in various magnifying powers. You might find an inexpensive set of those might help if you can't find the cheaters for the hood..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 dstevens I'm going to keep at it.
Reply:d,Just saw the post.DSW and others have given some good advice.  Just a few comments.Setup seems in line.  Agree with the comment about argon flow may be a little high.  For that weld I'd probably set flow at 15-18 CFH.From what I'm seeing, it may be necessary to go back to the basics and tackle one aspect of tig welding at a time.  By this I mean going back to puddle control and moving the torch without filler.  To do this, I'd start with a CLEAN coupon and take a straightedge and draw a line with your soapstone.  Initiate the arc and form a puddle,  move forward and repeat, all the time keeping your puddle consistent in size.  Use a coupon at least 6" long.  This will force you to move the torch with your arm rather than your wrist/fingers.  Once you can run the full 6" with a consistent puddle width and spacing, you'll be ready to start adding filler.  Don't know if your "at home" machine has pulse capability, but I've used pulse with new guys I'm working with to build timing.  I'd recommend a pulse rate of about .8 PPS (Pulse Per Second).Remember, with steel, there's not as much need to reduce your amps as heat builds in the material (unlike aluminum).  You can almost leave the pedal constant and control the puddle with the speed of movement.As far as filler feeding, I'd recommend taking a piece of filler and just practice feeding the rod.  Cut a piece in half and just practice feeding while you're watching TV.  It should become "second nature".  If you're having to be "thinking about feeding filler" you'll be focused on that rather than maintaining puddle consistency.On this thickness material, you DO NOT need to worry about beveling the edge of your coupons.  Not necessary.With steel 1/16" filler you can move it slightly further away from the arc without worrying about contamination (not so much with SS or aluminum).  Just make sure the puddle's melting the filler and not the arc.I've found that about 2 hours of concentrated practice is about all most new tig welders can handle at a time.  Then take a break and do something else for awhile and come back to it.  That gives the mind a chance to relax and think about what you're doing and how you can do it differently and hopefully better.  To just "keep on practicing" often times just means doing the same wrong thing over and over.When you're comfortable (and it WILL come) running a consistent bead (same size puddle and evenly spaced) without filler, then it's time to start adding the filler.I'm having a bit of a time understanding the heat issue when welding at 80A (or less).  Only thing I can think of there is that you're staying in one spot too long.  Lets see some consistent beads run with no filler.PS.  Myself, I'm nearsighted and wear no line bifocals, however the bifocal has almost no up close correction.  As a result I do not tig weld with my glasses on.  Just safety glasses.  As a result, I try to keep my work < about 18" from my shield, and often much closer (especially low amp SS work like handrails).Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Thanks again guys.  Real helpful, I appreciate it.  Found the cheater online.  The issue now is time.   I have one more lab to finish the steel before AL and 7 labs to finish 8 more projects.   I can practice at home all I have time for, which isn't much, but all the test coupons have to be done in the lab, using the settings speced by the instructor though I doubt he'd notice or even mind changing the gas flow.  I did OK on a 1F outside corner and acceptable on 1F lap but the butt and 2F T are killing me.  I'd rather learn right even if it means missing projects and potentially failing the class for not turning in all my projects.The coupons weren't purposely beveled, it happened when I knocked the dross off.  I was going to have another 100 punched at the place that does them for school but they are 10 days or so out.   I think I forgot to clean that coupon at all.  Sometimes I do that.  Bad habit to get into. No pulser at home, I've got a Square Wave 175.I hear you on the two hour limit.  What sucks about the Sat section is the lab can be 5-6 hours depending on the lecture.  Makes for a long day.  I'm beat after the first couple of hours so I try to pace myself.  Then I have to leave for the show so it's an 18 hour day.  Still, though, glad I'm doing it.   And I'm glad I can come here for help.  going back to the basics will be good for me.
Reply:No expert here but I just finished a tig class.  I wouldn't worry about gas setting.  You do want to remove mill scale back 1/2-3/4 " back from joint.  I would do this on both sides.  It's a pia and takes longer to prepare the coupons than to weld.  I wear glasses and purchased side shields for them, this satisfied the instructor.  I also added a cheater and fashioned a leather back cover for my helmet to reduce arc reflection from the safety curtain from lighting up the inside of my helmet.  I see no reason to be adding filler metal if you cannot do a decent consistent autonomous weld.  I know you are under the gun but rushing the process will not fix this.  The beauty of this methodology is once you get all the basics down with the mild steel, the stainless and aluminum will really be pretty simple.  The hardest part for me was the vision component along with how close the tungsten needs to be to the work.  Question.  Are you resharpening your tungsten every time you dip it in the pool?  Every 2nd time?  One thing I noticed when I get to class was the tungsten from the young guy class ( I am old fart)  looked like a piece of white dog ****. Since you have a long class, take a break and watch some of the students that seem to have a handle on it.  Also your instructor should be showing his skills and tricks.  Don't be afraid to ask, it is his job to teach.  Good luck and remain calm!
Reply:sundowns recommendation on gas flow is exactly where mine is usually set at, seems to work perfectly for this kind of thing. i think that the being comfortable and sliding your hand down the 'shelf' as dsw has said is waay more important than you think it might be-seems like its easy to get a little hungup and sort of react by rolling your wrist to try and keep the speed consistent..the angle and everything else changes when you do this. also, i agree that you shouldnt need to bevel at all, but the cleaner those edges are-the easier it is to slide the rod into the puddle(again, like dsw said) i think thats going to be a little easier to do at first than dipping
Reply:Update, how are you doing?