Dip spacing and bead appearance

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I was trying to find some old posts by Pangea about bead appearance and dip spacing. I thought I remember him talking about ripple pattern and stress risers. I'm not building anything that is going to the moon (or beyond) like he is, but I've been giving this a lot of thought and was hoping for some guidance and maybe open up some discussion on the topic. DSW mentions dip spacing often when he is providing feedback and I believe he likes to see a tight ripple pattern. I've been practicing quite a bit running beads on aluminum sheet and I wanted to see if this top bead is in the ballpark. I like the appearance myself, but should it be tighter than that? Are there accepted guidelines or does experience and the job at hand dictate the bead appearance?Al practice by Zanconato Custom Cycles, on FlickrIs the spacing here on this T joint a little too wide?Al practice by Zanconato Custom Cycles, on FlickrLincoln Squarewave TIG 1750.0625" thick 6061 sheet3/32" 5356 filler3/32 2% Lanthanated electrode, 9 series torch, gas lens, #7 cup, about 15 cfhamps set at 125, but I'm just using the pedal.Thanks in advance!
Reply:well, I can't tell you anything about stress risers but I have a question..in the last pic why did you stooped 2 times ? do you feed from the wrist or from fingers?I like the apearence of the top bead in the first pic, that's what I'm going for when welding alu... doesn't allways work --------------------------------------------------------------www.becmotors.nlyup, I quit welding.. joined welder anonymous
Reply:I was probably holding my breath and had to stop :-)I'm still trying to get comfortable to go for longer runs. That's one thing I focusing on when I'm welding on the sheet.
Reply:I asked the very same question before and the answer I got was its all personal preference. As long as craters aren't showing up or the weld gets to thin its fine.The only thing I would worry about with getting the humps to close together is the time spent putting heat into the material.
Reply:As far as dips, I was taught to keep them nice and tight, to add less filler more frequently vs lots of filler fewer times. I can't point to an exact reason for this  that I can quote however. Just the way I was taught.One thing I do see in the 1st pict with the dips farther apart is that you are loosing the edges of the bead and the dips aren't tieing together well. The general area is circled in red, and the are in blue is the easiest to point out.Top bead on that plate looks very nice. Fillet looks very nice also with the exceptions of the tie ins. They could still use some work. I see a few minor irregularities in the bead that practice will take care of.I frequently comment on keeping the pattern tight in mig. There I often see guys moving forward too fast for their motions and having similar issues to the circled areas where the toes of the bead don't tie in well as they move from side to side. Again faster, smaller motions will tend to eliminate this issue vs slower larger motion. there it's often clear when problems occur since if you gouge out too much material and don't stay in close enough to fill it back in, you create weak points and stress risers. You can end up with the same issues when going weaves or fillet with tig also.I will say the new night school instructor I'm working with lays his dips a bit farther apart than I do. Since the company he works for does valves and so on for US Navy subs, I'm guessing his "style" doesn't effect the quality of his work. He's complimented my on my tig beads, so I'm not concerned that our styles don't match up. 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:If you REALLY want to practice dip rhythm..Get a positioner.The speed will get you there FAST....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:zank#3  "I was probably holding my breath and had to stop" A year into my first job, decades ago, I was OA cutting a large beam on blocks off the floor. From behind and above I heard, "Who are you waving at", off course referring to my travel path.  I had been through a University welding program and thought I had the business end of tools figured out.  But it was this fellow that taught me, not only how to use a cutting torch, but to really weld.For OA cutting [standard for the day], 1) he said, "You should be so relaxed that someone should be able to lift the torch out of your hands, 2) and you must breath."  In welding, "If you don't/can't breath, you are not relaxed, and this tension shows in your bead, and limits your travel distance.""You are never going to be really good at OA or welding, unless relaxed, and breathing is key."You are developing a very good hand, I hope this help.Opusp.s.This guy was the best in the shop and all performance.  When everyone was jetting their detroit-iron like a 747.  He drove a Lotus Elan, then considered the fastest cornering production car in the world.
Reply:The T joint looks good; you are doing fine. If you do dips pretty consistently, you will find yourself coming out of the pedal less and less. Once you get a heat range working for you, and you start adding filler, you will see the pedal does not move too much. If I am pedaling, then this means I am fighting dirty material almost every time.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Originally Posted by zankI was probably holding my breath and had to stop :-)I'm still trying to get comfortable to go for longer runs. That's one thing I focusing on when I'm welding on the sheet.
Reply:when I move forward with the weld pool, I go to the leading edge of the previous pool. therefore time spent forming each pool dictates spacing, and since material stays the same thickness the amount of time stays the same and the bead is even.Dynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:It would also depend on what size filler you used.    TIG beads can also be made without the stack of dimes look and be perfectly acceptable welds...Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:re: stress risersEvery sudden geometry change is a "stress riser" or a pre-made crack-initiation site.  Those things matter a lot to highly-stress items or items where fatigue life is a factor or where the material(s) are crack-sensitive or fatigue-sensitive.A convex bead on a butt-joint is a stress riser.  The toes on a fillet weld are stress risers.  etc.For 'critical' stuff, the bead size and shape may be critical.Other times, not so critical at all.YMMV.  The best laid schemes ... Gang oft agley ...
Reply:Wow I think those beads on the flat plat are beautiful. I'm definitely a mortal among Gods.
Reply:to get that individual looking bead weld you need to get a  rhythm that incorporatesprecise movement of the torch after each dab/puddle......Filling the space with the exact same filler material each dab......the quick movement keeps any material from dragging over to the next dab/bead......In the beginning it takes concentration but after you practice the movement it becomes second nature.......Last edited by B_C; 12-15-2012 at 06:21 PM.  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Beautiful stuff, B_C!Hey, thank you for all of the feedback, everyone. I've been working on breathing first and foremost. And loosening up. It sounds like there is an acceptable window for dip spacing. Of course, I'll keep practicing.
Reply:For me running fast tight beads works for STAINLESS where the filler takes some of the heat away from the puddle........It looks cool also.....Not much into stainless stuff...I have a customer that makes semi-conductor stuff and that's about the only time I weld stainless.....I get real rusty on it because I only see him three times a year.....The rest of the year I'm sticking aluminum parts together...huge difference....[ame]http://www.youtube.com/watch?v=19xv64DH80g[/ame]I made a mistake in the video I use a 1/16 in 2% Thoriated tungsten and .032 308 filler there are holes drilled through the fixture on the legs so the argon can flow through the part.......Last edited by B_C; 12-15-2012 at 10:25 PM.  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock