BODY GUYS HELLLLLLP......Burn Through

[Bullitt-]

    Been welding my rear quarter patch panel on, 99.9% has gone fairly well but right by the depression for the rear bumper I'm in BURN THROUGH HELL..  I understand burn through & the primary issue is the metal is so thin here that once you get a hole you can chase it forever. Anyway I've managed to tame most of them but it's like there's just going to be a few holes no matter what I do.     

     What to do?...... I'm thinking a little epoxy metal would be safe.   

Thanks
Wade

[bb71challenger]

If the hole is not too big you might try triggering out some extra wire, cutting and bending it against itself a few times to make a "filler rod" of sorts. Then when you arc it should take the brunt of the welding current and not burn through. Of course you will have hairs sticking out but its not a problem to hit it again and melt them or grind them out.

[wagesofsin]

if you have a major hole, get an inert metal to place behind it. then you can fill it from the outside in. go slow, be patient. let the fill cool, go somewhere else, then come back and add more wire.
run more wire in the future, id rather spool more than fill. savvy?   
im not real good at 'splainin with a keyboard.

[Bullitt-]

If the hole is not too big you might try triggering out some extra wire, cutting and bending it against itself a few times to make a "filler rod" of sorts. Then when you arc it should take the brunt of the welding current and not burn through. Of course you will have hairs sticking out but its not a problem to hit it again and melt them or grind them out.

Ok I tried this....twice. First try I made the plug tight & pushed it 1/2 way in, welded ground down & it literally fell out & the hole was larger than before.    Second try I left the plug looser put the copper behind it & barely into the hole,  welded ground down & all looks well except there is new hole to one side.

 

if you have a major hole, get an inert metal to place behind it. then you can fill it from the outside in. go slow, be patient. let the fill cool, go somewhere else, then come back and add more wire.
run more wire in the future, id rather spool more than fill. savvy?  
im not real good at 'splainin with a keyboard.

No major holes... with the exception of the one described above I'm looking at about the diameter of a pencil lead at the largest.... That one had grown to 1/2" X 1/8" at the widest points but now it's all but gone.

I've kept the areas cool by blowing compressed air after every couple of zaps.

[E-Body Products]

Be careful not to grind too much.  You can get the metal too thin, thus creating an even bigger problem.  This sounds like why it is burning thru so easily.  I would try as wagesofsin mentioned and put some copper behind it.  This will let the filler build up without burning thru the metal.

dj1965
www.ebodyproducts.cm

[Bullitt-]

Be careful not to grind too much.  You can get the metal too thin, thus creating an even bigger problem.  This sounds like why it is burning thru so easily.  I would try as wagesofsin mentioned and put some copper behind it.  This will let the filler build up without burning thru the metal.

dj1965
www.ebodyproducts.cm

Little bit of both I suspect... one area I had been running my DA on orbital & ate right through the metal close to the bumper depression where no welding had taken place.. Still other areas where I had allowed 1/4" of flat metal below the depression just burned real easy, both of these I believe were caused by the stretching of the metal when pressed out... & I have backed with copper when possible, it definitely helps.

[torredcuda]

If you can get in behind to the back side with a piece of copper to block the hole and then you can weld right to that as the weld will not stick to copper,otherwise real quick zaps of the trigger pionted at the egde of the hole letting each one cool off will eventually fill it in-use a low heat setting and turn up the wire speed.