How do these sheet metal practice welds look?

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I've been practicing tack welding sheet metal the past couple of days.  I found this old file cabinet drawer that I cut in half and practiced on.  I'm not sure of the exact guage.  I was using C25 and .025 wire.  I only burned through a couple of times, and it didnt warp as much as I thought it would.  I tried to skip around to keep the heat from warpign too badly.  I'd just like to know if I'm doing anything wrong.  thanks!
Reply:Originally Posted by thefluxcorekidI've been practicing tack welding sheet metal the past couple of days.  I found this old file cabinet drawer that I cut in half and practiced on.  I'm not sure of the exact guage.  I was using C25 and .025 wire.  I only burned through a couple of times, and it didnt warp as much as I thought it would.  I tried to skip around to keep the heat from warpign too badly.  I'd just like to know if I'm doing anything wrong.  thanks!
Reply:that's hideous
Reply:Originally Posted by Nick Zthat's hideous
Reply:I think it looks pretty good. A sheet metal butt weld can be difficult. Most guys try to run a bead, which burns through and causes warping. Your jumping around, helped limit the warping a lot. Try to get your tacks in a straighter line, an AD helmet will help with that if you don't have one. When you do a real panel, remember that grinding the finished tacks can cause as much warping as the welding; so jump around there also. 9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:If youre concerned with it warping, try a back stepping method.....and start holding the trigger....geesh!only thing worse than an ugly woman is an ugly weld
Reply:Originally Posted by Craig in DenverI think it looks pretty good. A sheet metal butt weld can be difficult. Most guys try to run a bead, which burns through and causes warping. Your jumping around, helped limit the warping a lot. Try to get your tacks in a straighter line, an AD helmet will help with that if you don't have one. When you do a real panel, remember that grinding the finished tacks can cause as much warping as the welding; so jump around there also.
Reply:Oh my? Where to start?For sure moisture would find its way in from the back if you don't button those welds up.Make sure your metal is clean all the way, and your gap consistent and nominal, maybe 1/28th, while you want to avoid warping your sheet metal try running small patches of about an inch or less, and always orient your mig gun in the same manner each time for the most consistent weld.You should already know this?If you can reach behind the panel with a dolly, after you make your weld take the dolly and back the weld (from inside) and hit the crown of your weld (on outside) with a flat body hammer and it will reduce your warpage because mig welds are horrendous for creating stresses on sheet metal. A better explaination is like this:" imagine welding 1/4 steel with mig and having a weld with 5/8ths inch crown?"
Reply:this is backstepping..... Attached Imagesonly thing worse than an ugly woman is an ugly weld
Reply:Most sheetmetal on cars is a series of small tacks until all tacks make a complete weld. To help keep the warpage down you can also use a heavy towel soaked in a bucket of water. Tig tack welds put more heat in the metal were as mig tacks are fast and less heat. This is also a slow process, in time you will find you are doing better the more you do it. Grinding can be done the same way with the use of the towel to help cool the metal.
Reply:Originally Posted by thefluxcorekidwow, you're a douchebag.Yes, i eventually would like to tackle some body work, welding in patch panels.  I realize I need to weld the sheetmetal completely, and stack the tacks so it fills all gaps.
Reply:I made it pretty obvious last summer im no pro at body work....(bondo) I have never tried to weld body stuff but it cant be too hard. We do ICAR training, (not me) but I see the material they weld on and it doesnt look too difficult. They do train them to do full length welds and spot welds, on aluminum and steel.I have yet to see them do a bunch of tacks.only thing worse than an ugly woman is an ugly weld
Reply:They look great.  Automotive patch panels are typically "spot" welded in like this.  Miller, Lincoln and ESAB as well as their auto body offshoots have spot weld timers as options on their commercial size machines just for this purpose.  I wish they would have had this 30 yrs ago.  We torch welded or brazed everything back then and "oil canning" distortion was fun to fix,
Reply:That's a pretty decent start to a stitch weld. Once you get your spot welds set at say 1/4" apart, you can start a weld right on the edge of a spot, carry the weld UP ONTO THE SPOT WELD, maybe 1/8" and then back down to the flat and fill between the spots. You should get minimal burn thru that way, and then you sould also not get much warping. After that, grind and bondo. Don't worry about the guys hatin', they will drop it soon enough as you improve.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 El_LloydeoI made it pretty obvious last summer im no pro at body work....(bondo) I have never tried to weld body stuff but it cant be too hard. We do ICAR training, (not me) but I see the material they weld on and it doesnt look too difficult. They do train them to do full length welds and spot welds, on aluminum and steel.I have yet to see them do a bunch of tacks.
Reply:Yeah Ok it may look bad to some folks but its not bad for beginning welds especially when butt welding the two pieces with no over lap.Try overlaping the two pieces  it will help spread out the heat a bit better and aid in edge burnout.Keep up the practice with practice will come better control of all the factorsCo-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:Thanks for all the replies.  I'm going to keep practicing. Like I said earlier, the second section I tried (not pictured) was better than the first.  Little by little I was getting the hang of it better.
Reply:I hate to say it, but this may not be the right forum for auto body welding advice. Metal meet or the HAMB (jalopyjournal.com) are your best bets.First off, the "wet rag" technique is a big no-no. Putting a wet rag on a weld with just cause it to shrink faster, and possibly more. It will also make your MIG weld even more brittle than MIg welds inherently are. You definitely have to stitch weld, like you are doing. Try to keep the welds more in line, but penetration is the most important part. A small gap is helpful. I recommend getting some but weld sheet metal clamps. They set a very good gap and hold the metal in good fit up.Get a roll of .025" ESAB Easy Grind wire. I is not only easier to grind, but it also is easier to hammer and dolly, and doesn't crack as easy when plannished. I also find that it penetrates better and lays flatter at a given temperature than standard er70s-6 wire.The best bet is to get an o/a setup and a small torch like a Henrob or a Meco Midget for sheetmetal welding. I tack every 1"-1/5" with my mig, grind the tack almost flush, hammer and dolly out any distortion, and then gas weld the panel. I do about 3/4" solid bead at a time, and hammer and dolly the weld as it cools. Skip around a bit, and you will wind up with a very flat weld that needs very light grinding, and if you use the hammer and dolly to reverse the shrinking of the weld as you go, the panel will need very little filler.I welded this hood with the above mentioned method, using a Henrob torch. Its not finished in the picture, but its almost fully welded, and ready for some more hammer and dolly work in a few areas. its been done for a long time now, but used very little filler. o/a welds in sheetmetal are much softer than a MIG weld. An o/a weld is about the same as the parent metal, where a MIG weld is much harder and more brittle than the parent metal. That means when you go to hammer the distortion (reverse the shrinking by stretching the metal) with a hammer and dolly, its MUCH harder to stretch, and can crack when hammer and dolly'ing it.Last edited by Chad s; 02-16-2009 at 11:39 PM.
Reply:cant read all of your post
Reply:Originally Posted by ed maccant read all of your post
Reply:When I went to school, our instructors (autobody) hooked some welding instructors to do the sheet metal welding demo, with disastorous results", and after being funny! Devastating to our moral, they told us after proper instruction we would be making these welds. Some got it, some didn't, which is why it is now 3 trades where I live.Not to take anything away from the welding instructors, they worked on alot of BOP casing bowls and high heat,solid grinding discs....Just telling it before you jump on a unicoupe write off in your garage.They pull licenses for high strength steel mishandled now.Chad said alot, gotta watch work hardening, warping.Keep it small.Normalize as you go.If you get distortion you can fix it by using dime sized cherry red shrinks on the high spots outside the weld.Less work after.Some say when you understand how to shrink metal you can move it around anywhere.One of the credentials to pass was to cut out a large circle and forge in a new piece without being able to detect a repair from both sides unpainted.A body file works good for indicating stressed areas.Looks like you are removing alot but your not.One other tip may be to try getting a shrinking disc for your grinder from your supplier or ebay to help manage your distortion.Keep this in mild you be okay.
Reply:Thanks guys!
Reply:Dosen't look bad! Keep practicing!Ya gotta spend money to make money!