vertical lap joint

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Welding competition is coming up on saturday. I'm going for MIG welding, and for the most part I feel really good about everthing, except my vertcal lap joint. My current technique is an inverted U. I have tried diffent things and I can make the weld look like a z weave pattern, but then it is to big. We are welding on 3/16 plate. We are using 75/25 mix, but I'm not sure what machine we are using. We have multiple XMT's, Gunslingers, PowerMIGs both 255s and 350s. So whatever machine we are assigned to.I was just woundering if you guys had a good technique for this joint? And if this technique would work in this video.
Reply:I do my vert's mig welds with a upside down v  pattern...pausing at each point for a half second or so, also push the torch in to the root and out at the toe's. 3/16 plate is in my opinion still doable with downhill if you have enough amps. Is anything thicker available??Lincoln pro mig 180Lincoln Square Wave Tig 300/wp 20/home built water cooler Victor, Purox, Harris, O/A welding/cutting setupsVintage Craftsman drill pressVintage Craftsman/Atlas 12"x 36'' lathe7''x 12'' w/c band saw Everlast 140 st
Reply:Hello BlackGT97, I don't have any pictures, at the moment, to give you a good idea of how this actually looks when completed just right now. However, I have included a sketch of sorts to describe the motion. Your machine settings will need to be leaning towards short-circuiting transfer mode in order for this to work. It is essentially inverted triangles, start the arc at the root of the joint, draw the puddle out on either side of your start point and then drag it across the joint to a parallell point on the other side of the joint and then push it upward and back toward the center of the joint again. Repeat the process. Hope the sketch clears up this motion a bit. Good luck in your competion and best regards, Allan Attached Imagesaevald
Reply:Allan's technique is what I usually do. With thin 1/8" metal it ends up being a very tiny wiggle more than a triangle on a lap joint. Often it's so small  ( less than a 1/16") most students can't spot it when I do the first dozen or so. The big issue is can you see and read the puddle. I find students have the most problems when the get to vertical because the can not "see" and read the puddle. You can do "timing patterns" on flat/horizontal, but it seldom works vertical and overhead. As the video mentions, I watch the top edge of the upper plate and move as soon as I see the puddle melt back the edge. I swing over to the lower plate and then back. How and when I move is simply dictated by what I see and how the puddle is reacting..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