Need help welding corners on thin sheet metal

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I have a hard time getting a good weld on corners of thin metal. The problem is the weld bead is really high and requires lots of grinding to make it look good. I have played around with settings but just can't seem to get it right. I am running .030 wire with my 180 mig. Should I try some .023 wire? Also what kind of motion should I be using. I tried going in a straight line and also tried going from one side of the corner to the other using a side to side motion and both ways I was pushing and not pulling. I am also using gas. I have attached some photos for you to see what I am talking about. In the last pic I want you to tell me which of the 2 would be the best way to set up the metal for welding. I think the #2 pic is the best way but need to be sure. Attached Images
Reply:move faster or turn the wire down. if your really having problem weld 1/2 way and then start at the other edge and weld away from it until you meet the other weld. with enough time and pratice either weld method will work. the first is method will be easier but wont look as good. for the second method the fitment will have to be more accurate or you'll burn through.
Reply:Also if you use the push method you will get a flatter bead.BTS Welding
Reply:Use open corner joint, and put a small tack weld every three inches.  Tip the piece so that the joint is almost vertical and run vertical down keeping ahead of the puddle.  Move rapidly and don't turn your heat down.  Aim the gun about 45 degrees upward.
Reply:I'm thinkin turn the heat up and go much faster.  What size is the plate?   For set up, I prefer the second.  Both work and both are as strong to me.  I would weld both sides of the one on the left if it was thicker.  #2 is an outside corner joint.  Once you are good, you will be able to make look really nice uphill or down.Turn the heat up till  you burn through then back off a little.  Get a feel for what the settings do.  The end view shows the weld is just piled on the plate.  MORE heat More pictures DavidLast edited by David R; 06-24-2008 at 09:19 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Method #1 - To get it to look good, you have to melt all the filler you are adding into the melted zone where you have all the existing material.  So you pretty much end up with a 'high' weld bead.Method #2 - Now you have a place for the melted filler to go as you are welding.  But because your corner is just the two edges of the material, it's easy to burn right through the corner if you don't get your parameters and your coordination pretty good.Try a set-up about half-way between #1 (closed) and #2 )open).  Lay it out sort of like a lap joint so you have a bit of material in the corner but not all the way to the outer edge.Oh, and practice, practice, practice.
Reply:Use option 2, as said before.  From there, you just need to adjust your wirespeed, voltage, and travel speed.  If you are having to grind them afterwards to hide the weld, TIG may be the better process.  If you go to TIG, I'd go with a fitup inbetween option 1 & 2, so that one piece just sits HALF way into the other one...then fuse them without filler, or with very little of it.
Reply:Originally Posted by lotechmanUse open corner joint, and put a small tack weld every three inches.  Tip the piece so that the joint is almost vertical and run vertical down keeping ahead of the puddle.  Move rapidly and don't turn your heat down.  Aim the gun about 45 degrees upward.
Reply:I too would prefer #2 downhill.  If I had to fit up like #1, I would bevel both sides prior, if possible.
Reply:737,I agree fig # 2 is the way to go. First you need to get the power source dialed in. The set up you have will do a great job welding this thickness material. You can practice all day with the wrong settings and will just get frustrated. The .030 will work. NO need to change wire. No hijack intended. Thought pics may help. Welded vertical down settings as piced .030 wire 75/25 gas 20cfh 16ga mild steel.  frontbackend shot, not the best pic. Hope you get the idea. You can do it.Waldo
Reply:Originally Posted by Hammack_WeldingThat's how I do it.   I pretty much set it up as in #2  Tack it everythree inches or so and then take a hammer and tap the tacks to tighten the seam.  You want the seam touching for the full length.   gaps will result in burn thru.
Reply:Originally Posted by Waldarosa737,I agree fig # 2 is the way to go. First you need to get the power source dialed in. The set up you have will do a great job welding this thickness material. You can practice all day with the wrong settings and will just get frustrated. The .030 will work. NO need to change wire. No hijack intended. Thought pics may help. Welded vertical down settings as piced .030 wire 75/25 gas 20cfh 16ga mild steel.front
Reply:Personally I hold the gun straight in. Others may have different preferrencess.Miller DVI2Lincoln Precision Tig 225Thermodynamics Cutmaster 38Everything else needed.
Reply:Lotech and hammack have it right. I run pointing up, hot, and lead it down it. Seldom even need to hit it with a grinder with practice and voltage and wire speed just right. With practice you can do it on the horizontal as well and have a nice neat round edge. You gotta move quick though.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:737,Gun is pointed UP @ 5 deg. and as stated it is fast, and make sure you are on the leading edge of the weld puddle. Get in a position so you can weld to the bottom in one motion practice without pulling the trigger. Mig vertical down can cold lap if your not on the edge. Weld can look good but will lap over the base metal and not penetrate. More on a T joint than a corner. Hope this helps.Waldo
Reply:It doesn't look like your stock is thin enough to justify this BUT:Welding 22 gauge sheet metal with .030 flux wire with a harbor freight welder, I found it best to simply tack tack tack until you wind up with one bead (essentially tack every 3 inches, then go back and tack ever 1.5 inches, and so on until you have a solid weld).  It will press your skills as a welder and your patience as a tradesman.  Much easier to do with MIG compared to flux too.  And why was I welding 22 ga steel with .030 wire and a cheap welder?  I was bored.    I wish I had saved the birdhouse I made.  Front door looked pretty good too.  Thinner than 16 gauge sheet and you run a severe risk of distorting whatever you're working on if you try to draw a flat bead, regardless of how you tack..023 wire would be nice for your application but isn't required.  When you get to welding on some of the thinner more modern domestic and older japanese vehicles is when you "need" to step down that small IMHO.  I'm not a professional of course but I'm semi professional.  From the looks to me though you mostly need to turn your wire speed down.  Once you tune your wire speed a little lower you'll probably want to tune in your power setting.  Your Miller should have a little table inside by its wire spool that explains what settings your welder will work at and with what gauges of steel.  Use this as a ball park figure to get yourself started if you ever feel like you just can't find the right setting for the job.Just my $0.02.  I can easily agree with everything said above.