Weld shut or bondo very small holes in body?

[Mikes Z car]

When I removed the aftermarket mirrors the PO installed on my car three holes were left on each side of the car when I put a stock mirror back on the drivers side. Two workers at a local paint and body shop gave me different advice on how to fix the holes, what I would call the hard way and the easy way. The hard way is to weld over the holes and the easy way is to put body repair tape on behind the holes and bondo over them. The last time I welded over much larger holes the weld splatter damaged nearby paint a bit though the body shop has welder's paper they say will protect the paint. I plan on putting just enough bondo in the holes with a dab of paint on them to hide them to keep water out, I will not be feathering the surrounding area for now. I may paint the car later just don't have time right now.

My question is has anyone had experience with this they can share as to whether or not I can put tape behind the holes and have it work?

I think Eastman sells a small hole repair kit but it looks like it is for larger holes.

View looking straight up inside driver's door, the front of the car is to the right:

Holes in Driver's door:

Edited April 16, 2014 by Mikes Z car

[hr369]

anything behind the bondo to keep it from absorbing moisture inside the door is a good thing.

i've used masking tape before as a backing until the bondo set up. then pulled it off and

painted the bondo from the back side.

i'de indent the holes a little before bondo'ing.

soldering them would be my preference though.

Edited April 16, 2014 by hr369

[Mikes Z car]

hr369,

Indenting the holes seems a good idea. I had forgotten the soldering option. Is scraping the metal clean and using acid core solder sufficient preparation for soldering? Do I need to back the hole with a steel washer or something while filling in the hole?

Mike

[ajmcforester]

solder/bondo why not weld you need to clean the metal either way; welding is the most solid method. With solder was used for areas you could not hammer out (like door frames), bondo came as a cheaper way to do the same thing. The problem with both to fill the hole you will need to build up the material on the inside and top. So when you paint the bulge will show. If you weld then crush the weld and a little hammer work you can make it smooth then use a fallible primer.

[Stanley]

I don't have the skill to weld it without making it worse, so I'd use JB Weld. Maybe get a little stainless steel screen for faucets at the hardware store, or cut a little piece of galvanized screen and stick it on the back with some JB Weld. After it sets solid, fill it in from outside with more JB. A little bondo to finish it off since it sands easier, then some sanding primer.

[hr369]

i used just standard acid core solder for plumbing.

fast forward to 6:25 on this video. it shows how to solder holes up

in sheetmetal. this is old school for sure. dent puller and solder .

yes you could use a washer as backing on the larger hole.

Of course this is not the preferred way to repair. welding is the best

but you said you did not want welding sparks to damage your paint.

another option is if you could take the door off the car and mig weld it up.

to minimize the heat damage to the paint you could use a moldable heat

dam around the weld area

[Mikes Z car]

Thanks for the video on soldering.

I learned the welding paper that protects paint only works if the surface is vertical and the door in that area is somewhat horizontal so unless I want to take the door off I don't think I will try welding. If I were sure I was going to paint the car soon so I didn't have to worry about the paint I would try the welding. Might try the JB weld. Thanks to everyone for teaching me options.

Mike

[Big sam]

You could try protecting areas you don't want effected by welding spatter with dampened bath towels. This has worked for me before.

[cbuczesk]

You can use damp towels, cardboard, tape, etc. to protect the paint and glass. Welding is the best way to fix it. For a temporary fix I'd "V-out" the hole, put some tape on the back side and fill with plastic filler. It might be a challenge later to remove the JB Weld too.

Chuck

[Mikes Z car]

Good thoughts on the damp bath towel and the JB Weld. Will try welding first. Thanks for all the great ideas I couldn't have learned this much by searching on the web.

[ZCurves]

Mike, While JB Weld is a intriguing thought, I suggest welding/brazing to do it right. In my own restoration, I had the holes brazed and then lugs placed in for my mirror to bolt to. Bondo will sometimes fracture and leave spidery cracks in the finish + let moisture in. BTW, I am impressed with your interior door picture. I know firsthand how tight the space is there - great pic.

[Mikes Z car]

I forgot when I welded shut the larger 1 inch holes on the back hatch from a wing I took off I ground down the welds with a dremel which wanted to jump around and hit the paint. Had to replace the drive belt on that dremel. The smaller holes would make it more difficult to avoid the paint so I will try something else to fix the holes. Want to keep water out until I can paint the car. Right now the back hatch just has duct tape over the wing holes. Might be a candidate for a mention on the red green show, they like duct tape.

Thanks for the compliment on the picture. I got lucky, just stuck the camera in the door and tried a couple of angles since I couldn't see the viewfinder.

Typed in brazing in a search engine, ran across this thread on sealing up holes:

Filling holes [Archive] - Classic Car Restoration Help Forum - Eastwood Shop Talk