Stringer beads on pipe

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I am trying to qualify on 2 1/2 in. steel pipe, in the 6G position. The root is with 6010, the fill and cap are with 3/32 7018.  I am good on everything, except the cap.  If I watch the puddle, I can't see where I'm welding.  If I center, on the toe, of the previous bead, I end up watching that and not the puddle. Does anyone have any tips to help me with a smoother cover.
Reply:One of the smartest weldors I have ever met (who was also my former boss and welding mentor) once explained that, when welding, a weldor has to be able to constantly and simultaneously monitor and control no less than ten different things:1)  the leading edge of the puddle2)  the trailing edge of the puddle3 and 4) both sides of the puddle5)  the joint ahead of the puddle6)  the bead behind the puddle7)  how much metal is in the puddle8)  arc length (or contact-tube to work distance for GMAW)9)  Torch/Rod/Gun angle10) travel speedThere's no real way around it, you simply have to practice and master being able to control all those things at once. Yes, it's difficult. If it were easy we wouldn't have such a shortage of skilled weldors.If your problem is not so much in watching all the right places but in actually seeing the puddle/joint/arc you might want to take a close look at your hood. If the shade is too light, the glare will wash out the view of the puddle, too dark and you won't be able to see anything but a faint arc. Also check, and replace, the clear cover lens, they get crudded up with spatter and smoke very quickly making it very difficult to see everything. Don't be afraid to spend a few bucks a week on new cover lenses in order to have a clear view of the weld.If it's any help, I found some pictures of a similar lab objective I did when I was in school (TSTC - Waco). It was 6G on 2" boiler tube (something like 3/4" or greater wall thickness) with a GTAW root/hot pass and 3/32" E7018 fill and cap done to ASME acceptance criteria.(Click all images for larger view.)This is the left side, done left-handed, with ballpoint pen for scale (no dime, all my money went to tuition):Here is the right side, done right handed, so it is much smoother:Here is the bottom, not as smooth as some of the later ones I did, but you can sort of tell that all the starts are staggered, i.e. they don't all start at the very bottom, this prevents any possible weaknesses at the bead starts from being all concentrated at one point. (The right side of the pipe is on the left in the picture and vise versa.):Here is the top, note that all the craters are filled to the full weld cross section (hesitate at the end of the weld to give the puddle time to fill in before breaking the arc):----------TensaitekiAAS Welding Technology - Texas State Technical College - Waco - 2007Visit Tensaiteki.com
Reply:Sounds like your lens is too dark if you can't see your puddle and and enough of the area around it to tell what you are doing. I went to plastic cover lenses a long time ago. Do they even still make glass ones? Plastic lasts forever compared to glass.
Reply:Believe it or not they still do make the glass ones. I couldn't believe it when I saw them last week while looking for the inner cover lenses for my new hood. Still haven't found those, grrrr.As for your problem, this is a bit of an oversimplification, but if you take care of the edges - the middle will take care of itself. Mostly it is just practice, practice, practice, and make yourself focus on the areas you know you need to be working on.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:I've been running 2.5 - 3 in schd 40 pipe everyday for the last 3 months.  I'll take some pics of how I do it if you want. But the lowdown is this. After the root I use 3/32 to do hotpass, making sure I dont fill all the way flush. I try to leave 1/16 - 1/32 lip before being flush. this lip is called the witness. It serves a few purposes, one being a guide to see where you are going. So using your 3/32 7018 for a cap, just follow the witness, its real easy to see so you can concentrate on your puddle and still see your lip. If you are using 3/32 then you are going to be doing 2 stringers, so after the first stringer take a grinder with a combo disc and very lightly grind around the top of your first pass. This will create a very shiny guide for you to see and follow for your final pass, allowing you to concentrate on your puddle and still being able to see where you are going. Dress up your beads with a file and your done.
Reply:What kind of amperage is good, for the 3/32 7018, on sch. 40, sch.80 and XX heavy wall. My beads tend to have alot of high spots, so I would like a flatter bead.  Also, the machine I'm using is a Miller CST 250. It has a stiff and a soft setting. Which would be best for a cover.
Reply:I usually run 3/32 7018 @ 90 -100 amps on pipe sked 40 and up though I normally use 1/8th for sked 80 and even 5/32 on XX, but would recommend you start at about 80 and work up from there to see what works best for you. Heat settings and travel speed can make a huge difference in appearance, but mostly it's just lots of practice. If you can't see the pass below and the edges of the bevel as you are welding one of two things is your problem: A. either your lens is too dark, or B. you need glasses. You shade your lens to the size of your work and the light conditions you are in. Well, actually, your lens could be too light, but that would be an obvious problem to you.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:Oh, regarding the stiff and soft I believe that is called inductance or arc force. Never saw the stiff and soft on a machine. It controls the wetness of the puddle and on the two machines I have with it the adjustment is done with a knob from low to high. I get my best results with it turned all the way down which should be stiff on your machine. Try both and see which gives you the best result.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:West coast hit the nail on the head with the depth of the hot pass and also the grinder suggestion. I've done this many times and it makes all the difference in the world when it comes to uniform stringers. Another suggestion along the same lines is if you don't have a grinder, just run a line of soapstone around the edge of the previous stringer to give yourself a guide also. Good Luck
Reply:I run all my out of position pipe same as westcoast welder.
Reply:Its like any process with a cap be it Tig Stick or Mig per application..You have to learn to look where you are..Look where you were...And look where your going all at the same time.....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:I took your advice, on the fill and the grinder, and I have made some improvement.  After grinding the toe, of my first bead, I could actually watch the puddle and see where I was going.  Thanks for the help.
Reply:Originally Posted by Jess92345My beads tend to have alot of high spots, so I would like a flatter bead.
Reply:Oh, regarding the stiff and soft I believe that is called inductance or arc force. Never saw the stiff and soft on a machine. It controls the wetness of the puddle