Fixing Screw Holes on Top of Cab

[davbell22602]

I'm not a body repair pro but how you repair the screws on top of this cab where someone added roof top marker lights? The screw holes goes all the way through inside the cab. I was thinking body filler but it would leak over time.

[BobbyFord]

They need to be mig welded

[davbell22602]

They need to be mig welded

Just mig weld over the holes from the outside and inside of the cab?

[BobbyFord]

If you can, get someone to hold a flat piece of copper over the hole from the inside, then mig the hole closed. The weld will not stick to the copper and will allow you to use circular formation to close the holes.

[davbell22602]

If you can, get someone to hold a flat piece of copper over the hole from the inside, then mig the hole closed. The weld will not stick to the copper and will allow you to use circular formation to close the holes.

Ok Thanks. There small screw holes about the size of the diameter in a #2 lead pencil.

[dunn71]

The way I do it is I pull a nail up through the hole and mig weld around the nail , then cut the nail off with a grinder. It works pretty good. I removed all the trim from my truck and this is how I filled in the holes. After you are done they may need filler in a few places, I used JB weld for that.

[davbell22602]

The way I do it is I pull a nail up through the hole and mig weld around the nail , then cut the nail off with a grinder. It works pretty good. I removed all the trim from my truck and this is how I filled in the holes. After you are done they may need filler in a few places, I used JB weld for that.

I really dont wanna use body filler. I'd rather cut out patches and weld them in with several weld beads. Then grind the welded beads down to surface level for painting.

[tylerb43]

MIG welding is not your only option. If you're going to weld them, go with Bobby's suggested method of using the copper backer for a plug weld. What I don't like about welding here is the top of the cab is super thin gauge metal, and it doesn't take much heat at all to make those molecules start dancing around and pushing on each other, leading to a warp or a wave.

Another method is to use 2-part panel bond (3M 8115). For example - if a single hole, cut a 1x1 or so piece of 18 ga patch and glue it to the interior side of the cab roof. Hit both mating surfaces with 36 grit first. Don't get this stuff on your hands - wear nitrile gloves. The glue will push up through the hole, filling it. After cure, sand and glaze coat the top and you're done.

I know, I know, it sounds weird, but trust me - this stuff is the real deal and it will not fail if properly installed. It's modern science at work, but they'll always be people who swear by what they know and are comfortable with. (until they try something different)

[davbell22602]

Well When I was my Carquest paint store the other day . The lady said I should try this putty that hardens up to metal. She said you grind, snad, paint, etc. over it. She also it also holds with no signs of coming apart. She also said some guys used it to on there engine parts. It comes in a little box that a golf ball would fit in. Its around $20 here for it.

[BobbyFord]

If you take your time with the MIG welder and just use short, small zaps alternating from hole to hole (not trying to fill one hole completely in one zap session) you will not warp the metal.

[72BahamaBlue]

I doubt you'll have any problems, as Bobby says...short zaps, copper backing. Careful when grinding, that's likely when heat warp may happen. Wet towels may help. Be sure to cover any glass, sparks from the welding and grinding will cause nicks or worse.
There once was a product called Moistbestos, for keeping panels cool when they used to gas weld, I suspect it's not available anymore!

[Montana71-F100]

If you have access to a TIG welder, the holes would be very easy to fill from the outside using either steel or silicon bronze rod.

Some other ideas without welding are:
1- Put epoxy on the threads of screws that match the holes and screw them in the holes. After the epoxy sets up, grind the head of the screw off. Grind a little at a time because the friction from grinding could burn the epoxy.
2- (probably better) Put epoxy on the the threads and the under side of the heads of screws (or nails) and put them in from the inside. Then put epoxy around protruding points on the outside. After the epoxy sets up, grind down the points from the outside. Before starting, make sure the paint is sanded to the metal so the epoxy will stick.

[cdeal28078]

There was a fabric we used all of the time when I was with the power company called Frazzle Cloth. It was gold in color. We did soldering and brazing on the generator windings and used this stuff cut in strips and soaked with water to keep from heating up the insulation of the windings. It will not burn. You can use it as a heat sink on metal when welding to absorb the heat and keep the metal from warping. I still have several yards of the stuff and use it whenever I weld.
clint

[Hawkrod]

The way I do it is I pull a nail up through the hole and mig weld around the nail , then cut the nail off with a grinder. It works pretty good. I removed all the trim from my truck and this is how I filled in the holes. After you are done they may need filler in a few places, I used JB weld for that.

I really dont wanna use body filler. I'd rather cut out patches and weld them in with several weld beads. Then grind the welded beads down to surface level for painting.

I wanna shake the hand of the guy that can do that successfully. Metal finishing a roof would not be impossible but unless you are a pro body man with 50 years under your belt there ain't no way you are going to succeed. What your talking about is a rare artform and requires skills that probably less than 1% of all the body men in the world possess. Hawkrod