Fibreglass?

[hillbilly67]

I've got big holes in the front fenders, and for some reason, about 50 nailsize holes on the lower half of the box (must have been rock chips that rusted thru) Welding up all the holes would take about a year!
Finding parts within a reasonable distance seems to be out of the question, so I kinda have to use what I've got.

Here's where the redneck comes out in me...I was thinking of sticking a fibreglass sheet over the lower half of the body, just up to the bump. (not looking to make a show truck, just a daily driver) Also, I wouldn't have to worry about rust ever coming thru. I've done this on an aluminum boat that had a bunch of pinholes and it came out fine.

[Banjo]

As long as you get all the rust/debris/grease off first it should stick just fine. From my exp with rust holes, even if you did try to weld, they would just blow through and get larger, as the metal is thin in that area. As for pinholes, once clean, i've had luck with fiberglass reinforced filler like bondoglass bridging holes and filling pretty well.

[rjewkes]

are you shure those aren't trim holes? are they only on one side?

[DuckRyder]

Por-Patch...

[averagef250]

Fiberglass works excellent for what you have in mind. I remove the body part, sandblast it, tape the holes with masking tape from the outside, lay down the sheet on the backside of the part and pour on the resin. You can do it with the part vertical also, but the resin doesn't always like to get into nooks and crannies.

Glassing is pretty time consuming as well. If you glass the parts from the outside you'll be sanding alot of fiberglass when doing your bodywork. Fiberglass dust is the nastiest stuff you can breath.

To weld body holes, even in very thin rusty metal you can find yourself a good size chunk of copper to use as a backer while you weld. You can weld right to the copper and work your way out until the entire hole is filled. The copper won't stick, atleast not well enough that a small hammer tap will knock it off.