Well, I went out yesterday and finally bought a welder. It's a Lincoln 125 Plus MIG unit, with the cart, self-dimming face shield, etc...I'm really happy with it. The first project I want to finish is welding trim holes up in a set of Caprice doors (where the rub molding used to be). I intend to practice quite a bit before I have enough confidence to attack this project, but I'm just wondering what's the best way to 'fill' holes. Do I need some copper to back the holes up? Any recommendation on wire speed and current? Thanks!

------------------
Tony Nausieda
1970 SS 396-350hp

Since you said you were going to practice before you start this project, I suggest you practice this way:
Practice on the same size/shape holes in the same guage metal.
Try filling it with the wire only.
Try welding small metal plugs into the holes.

After this exercise you can see which leaves a better patch. I believe you will get a better patch with the plug method - especially on 1/4 inch or larger holes - with less chance of burn through.
Just my opinion based on my limited welding experience.

------------------
1967 Malibu
1967 Impala SS396 Conv.

"I long to accomplish a great and noble task, but it is my chief duty to accomplish humble tasks as though they were great and noble" - Helen Keller

This will not get me any restoration points, but is what I normally do.

1. Use a disk sander to remove the paint around the hole.

2. Use a small rat-tail file to clean the inside "edge" of the hole (you can't weld to something that is rusty!).

3. Cut pieces of sheetmetal that are larger than the hole and use duct tape to hold them in place on the inside of the panel. (make sure that there is no surface rust on the filler plates)

4. Then, quickly throw a spot weld between the fender panel and the filler plate.

NOW READ THIS CAREFULLY!! If you do the spot weld quickly, the tape will hold long enough. If you put too much heat to it, the tape will let go before the spot weld is done. Too much heat can also set the tape on fire!!!!!

5. Once the spot weld is in place, remove the tape, and be careful that you don't burn your hands. DON'T leave the tape there, or you may set fire to it latter while doing the finish (fill) welding.

The only place where I wouldn't do this method would be in the trunk area where the fill plates could be seen. They are real ugly!!

Once everything is said and done, spray the inside with a good (3M) sealer.

On the safety side; keep a couple fire extinguishers handy (not just hanging on the wall). Try to have somebody keep an eye for stuff that starts smoking. To prove that I'm not trying to preach, over the years (48), I've set fire to carpet, undersealer, and my hair! You don't see much while an arc welding mask is on (but you will smell your hair burn).

------------------
Wes. Vann
Technical Reference section
Gold Member #5

If you have a metal scrap yard in your area that get manufacturing scrap. go get an assortment of metal slugs ( punch outs )
for .125 in or smaller holes just plug weld. or make yourself a copper/aluminum backer. the other method slug/PLUG work well also. I picked up a Super magnet that works great to hold the plug/slug patch to you weld it in, glue residue is so MESSY. As for fire prevention. I have a CO2 bottle right on the welder cart.
Wayne

------------------