steel gauge

[Tundra]

What steel gauge should be used when repairing a fender/door etc. A patch needs to be welded. Is zinc plated or galvanized steel OK or should it be plain steel. Thanks for input

 

[dang]

Not sure on the gauge, but you shouldn't use plated steel. Unplated with a sealer/inhibitor after the welding is fine.

 

[vraned]

I use 18-gauge (0.048") cold rolled steel.

 

[Bill Riblett]

I use 20-22 gauge zinc-coated most of the time. This requires a little extra effort to clean the edges to be welded of the zinc coating first and I wear a respirator mask when welding because the zince fumes are toxic. Here in the mid-Atlantic it is humid and we get about 3" rain every month, so it is worth it to me. I use 18 gauge for structural repairs, inner rocker panel edges for example. The body sheet metal is not that thick.

 

[BarryG]

Bill, When you weld , which method do you use? Tig / Mig and what wire are you using?
I ask because when you are grinding off any buildup of weld you might get the panel hot and distort it.
Thanks

 

[Bill Riblett]

I have a couple of MIG welders and usually use .023 wire; I think it is ER70. The smaller diameter wire both limits the amount of heat and makes a smaller bead. My first MIG, bought about 25 years ago, was really made for heavier work. A few years ago, I bought a 110 volt Lincoln and it both made welding easier and did a nicer job on thinner metal. Now I don't use the old Systematics machine on anything less than 1/8" thick.

If I am doing exterior sheet metal, like a fender bottom, I tack the patch in place and then weld short beads, about 1/2" long, skipping around the patch to keep the heat down.

I usually use flap-wheel disks to grind the welds and they don't generate a lot of heat. I also learned my stud welder works pretty well for shrinking small areas if that is needed.

 

[Tundra]

Thank you all. That's exactly the info I was looking for. I'm sure it will help others.