Patching holes

[Normspeed]

OK, I'm not experienced at body work although I did some amateur repairs back in school daze. Now, my car has a few screw holes that need to be filled. Some are from trim that was removed over the years, some were drilled by a prior owner, like when he decided to mount the license plate on the tailgate. These are generally 1/4" to 3/16" screw holes.

My question, is it acceptable to use something like Bondo to fill these small holes, or is it necessary to weld up the holes first? I'd like to get started on some of the minor body repairs that I can do without a garage and a welder. This is not a restoration job, just a fix up clean up.

Your opinions/tips?

[BobT-47P15]

Evidently there are some types of body filler that are better than others for the purpose you stated. I bought some type of filler once (don't recall what it was)......son-in-law who knows body work....said not the right stuff.

I don't know what the right stuff is, so you might want to check around with someone knowledgable.

[grey beard]

I am in the middle of major body work as we speak - I write - whatever. The "right stuff" is Duraglass or it's equivalet. It is used ordinarily by marine folks for fibergloass, and is totally waterproof. My suggestion on the coupe is to take a body pick hammer and countersink each hole you wish to fill just slighly, so the rim or metal edge is below the finished surface. Get your 4-inch grinder and grind a few inches of clean metal around each hole, then fill the holes with this stuff. It is quite stiff, and will fill major holes. When it dries, it is like iron to work down. I would carefully grind this stuff down so that it is just below the finished surface - or alternately scuff it down with 36 grit paper. Then use your conventional WalMart bondo or its equivalent to do the final gody work over top of the Duraglass.

There is a forum like ours dedicated to auto body - autobody 101.com. It is incredible - divided into sections for paint, welding, tools, primer, etc. Experienced body men monitor this forum and answer questions asked by normal street folks. Very interesting.

I restored a 71 Mustang several years ago - welded in new quarters and each had a 76 inch long seam that needed to be covered. I asked this group how to keep it sealed so moisture would never get in and their response was Duraglass. I've used it ever since, and have filled many holes on my B!B with much success. Jost remember to countersink the metal first, and grind a clean spot for it to adhere. You will ge impressed with the toughness of this stuffl JMHO

[Plymouthy Adams]

Even if you are able to get behind the panel with the holes and seal it, it is still not wise or cost effective to shortcut the repair if you have the means to weld the holes up. If you decide to braze instead of weld, be sure you get ALL the flux residue from the weld area as it will grow hair very similar to you favorite bread mold...Bondo is very much like brake fluid as it will absorb moisture from the air as the panel heats and cools so if moisture is able to condense..well..it sucks it in..then when the sun hits the next day..it will draw the moisture right on through and blister your top coat...I believe everyone has seen examples of this.

[Young Ed]

Some places I've read say to never fill with body filler because it will shrink and fall out. However I know people fill that small of a hole and get away with it. On the chevy we used a little bit of this stuff called kittyhair. Its bondo with strands of fiberglass mixed in. You mix hardner in it like bondo. That stuff seems tough enough to fill a hole like that.

[Tony_Urwin]

I wouldn't even consider bondo for holes. Back up the hole with a piece of copper, and weld it closed. Takes all of about a second with a MIG welder and after it cools you can grind the weld flush with the sheet metal. It's really faster than bondo and the repair will be permanent and undetectable.

[Norm's Coupe]

Norm,

Pick up an epoxy repair stick to fill those holes. Comes in a stick anywhere between 4" long and 7" long, in a plastic tube. Pull the stick out to the tube, cut off a small piece, then kneed it in your fingers. Once it's all the same color, shove it in the hole and let it cure. The stuff sets up in about 10 to 20 minutes. After that you can sand, drill or grind it all you want, then paint it. As long as the metal is clean that you put it on it will hold. Great for filling small holes like you're talking about. You might find it in a hardware store labeled as plumbers epoxy putty, same stuff, just a different color. The plumbers sticks sell in the hardware store for about $3 or $4 per stick. You'll find similar sticks at some auto parts places advertised for about $6 to $12 per stick. Think Eastwood is one place that sells them at the higher prices. It will not shrink and fall out, unless the hole isn't clean when you apply it. It's sold for industrial applications as well to plug holes and cracks in water pipes, steam pipes, chemical pipes, steel drums, etc.

[rearview]

The gas tank stop leak stuff works good for those holes. If you're handy with a torch solder the buggers up and never wonder about them again. Had to do about a zillion of the same trim holes on an old caddy that I had. Got pretty good by the end.

[Normspeed]

Thanks, great info. Welding is not an option right now. I'll chew on this info for a while, hopefully this burst of bodyworking ambition will pass before I mess something up.

Couple years ago I had a decent shop lined up and money budgeted to fix all the worst spots on my wagon for a fair price. Unfortunately, family medical needs took priority and the work never got done, nor is it likely to happen any time soon. It would be such luxury to just let a shop do this part.

[250440ND]

Regular Bodyfiller is talc based and will absorb moisture do not use where moisture can get to it. If I didn't have a welder I would try to 1st; countersink the hole and try to solder it shut or put in a screw or rivet and grind the head down almost flush and then add a filler such as "ALL-Metal" that has aluminum in it, very strong and won't absorb moisture or something like Dura-glass that is also very strong and moisture resistant, then grind that down and use a polyester glaze coat over it to finish it off. Just make sure everything is clean and follow directions on whichever product you use and you should have no problems.

[55 Fargo]

Evercoats kitty hair, will work, fills holes up to 3/8 or so. Possibly you could clean up the back of the panel, use fibreglass and cloth,then go over the top portion with a thin layer of kitty hair, or metal to meatl filler. It is always best to weld in holes, but there are other ways to fill holes if you can't weld them in...........Fred

[55 Fargo]

Another thing Norm, as I mentioned, do you have access to both sides of the panel where the screw holes are, if so use a wire wheel, grinder, sander with 80 grit, clean up both sides. Then use phosphoric acid and give it an acid prep. Fibreglass the are from behind using resin and and cloth, apply a few coats of resin, on the outside surface use filler or fibreglass filler, apply thin coats sand and feather edge, primer and spot paint. Norm this would give you a temporoary fix, if you can't weld it in. The thing is it can be repaired with welding at a later date, when you get that fancy paint job on your entire car...............Fred

[Normspeed]

The worst set of holes is in the tailgate, and it's not possible to get inside it. Years ago, the original owner got a ticket because the trailer ball obstructed the license plate. As the story goes, they relocated the tag to the tailgate, and added a truck clearance light above it. I've since put the tag where it belongs but the tailgate looks pretty bad. There is no rust or moisture problem in that area so I may get by with Duraglas and a skim coat of filler. I really appreciate all the ideas.