Yes I searched. . .probably not well enough, but I didn't find much on using epoxy resin as body filler. I happen to have some West System Epoxy Resin I was thinking to use to fill in my door seams. It's definately tougher than any bondo I've used.

I've replaced/repaired nearly the entire passenger outer cab shell to door post seam. . .and though its alot better as far as rust. . .it looks horrible In that never ending pursuit of perfection I've started to screw it up more than I'm helping it, so I'm cutting my losses. . .

I've decided to fill/fair the seam into the cab so it looks like a solid peice. I'm also going to fill the other major seams as well, probably lead/weld though.

Anyways, I'm familiar with Epoxy (been using it in wood construction for a long time) but not so much in conjuction with metal. What kind of prep work do I need to make it stick. . . well, forever?

 

Same as bondo.

 

If the epoxy you're using has some flex to it and works with the paint solvents...maybe. To the steel is a must for prep, the newer flexible body fillers would be a better choice. Lead is forever...and a wonderful thing.A lot of work,more complicated, but being a custom painter, I LIKE LEAD. But for the most part, the new fillers are very friendly to all the automotive finishes. Epoxies come in hundreds of formulations, I love them for a lot of things...but why experiment on something you want right.

 

Not a whole lot of flex. . .the stuff I have gets pretty hard. Could you reccomend a tough yet flexible body filler? Its been a few years since I did my truck, and I don't remember Bondo being all that impressive

 

I don't know if you remember the custom van scene in the 70's...? They used to fill all the body seams with bondo. If you looked close, you could usually find cracks. The custom bikes with the heavy molding would do a lot of the same thing. But the "bondo" got better, I hear the new UV cured stuff is not too bad. The old EVERCOAT company has changed their formulations in a lot of their line. I like the new featherfill primer and their flexible polyester spot putty. As far as body fillers (bondo) go, stay away from the cheaper stuff, look for "flexible" fillers. Almost all the major paint companies have a filler, some even have a complete line from metal prep to final finish...it's good to know there will be NO surprises hiding in the finish. I'm partial to RM, Ditzler and House of Color, at least for now. There are new names all the time. And as for prep, sandblasting done right is hard to beat.But body grinding discs are decent, just the paint, you can warp the metal if you get carried away. (red or blue steel is not what you want to see). And the deeper you get th filler into the seams, the better.

 

70's? I'm a young blood then I guess. . .my parents hadn't even met in the 70's lol. As far as cracking, I'm planning on filling what I can by welding the seams closed, on the big seams I'm thinking I can atleast put some stitch welding on em to help reinforce them to prevent cracking due to separation. I've already welded in solid the rear big cab roof seams. Looks sweet I dig the smooth look

Those fillers your mentioning, can they be ordered online? I'm going to be ordering a chunk of material and parts come the new year, might as well throw some body work astuff in so it all comes in at once. . .

 

Sounds like you're right on with the stitch welds, sounds about like what I have started on my 66. Building bikes, custom paint, car shows, girls...m-m-m, I had a lot of things to do in the 70's.But I still have a lot of paint jobs in this head... As for ordering paint, I'm not sure. I'm guessing yes,if I find out anything I'll yell...

 

using epoxy filler isn't really any different then working with bodyfiller, other then you need to get the mix pretty close. We used epoxy filler at a marine place I worked and it came in two parts, each in gallon cans which should be mixed 1 to 1. I think you should weld any seam solid no matter what you use as a filler, just cause there will be some flex in that area without welding it shut, and the filler and the metal wouldn't flex the same, most likely developing a crack at the seam eventually. I would think filling the seam first with an epoxy adhesive followed by a light skim of bondo if needed would be second best to welding. Haven't seen how it lasts long term though. But of your welding them already, why not just weld them up, take your time. Maybe if you do a good enough job and limit warpage, you can build up the weld and do a little metal finishing and not use any bondo on them. Take it slow, limit heat buildup, straighten as you weld, and even use something like heat sponge or wetted towels around where you weld, and who knows, maybe primer will be enough. Go to metalmeet.com and read a few of there posts over there about metal finishing. Something to work towards, using no filler at all. Something I may just work more on achieving in the future myself.

 

I'll try and get some pictures of what I'm talking about. . .that would be a whole lotta weld to fill what I'm after lol. Appreciate the link as well. I'm trying to get to that point of needing at the most minimal filler, but I started doing more harm than good on this part of my cab

. . .just gotta learn when to quit

 

I wouldn't use the west system stuff on a car. It costs a great deal more than ordinary plastic body filler.

However if you just wanted to, the wood in a boat would flex and expand far more than the metal on an auto, so I would expect that it would work just fine.

I don't think you will have any trouble getting it to stick, when I finished my boat I had epoxy resin everywhere, and it seemed to stick to anything it touched.

The resin shouldn't change shape any more than plastic filler. It's pretty tough stuff so I don't really see it cracking in the near future, but I've also never used it on steel. It works fine over brass and copper, but boats don't get the same kind of abuse that trucks do.

 

I've done glass,...hand layed and shot it with a chopper. I've done boats, trailers, trike bodies, race car parts and helped build molds for them. Custom bikes from the frame up, custom paint, welding, sandblasting, and helped a bit with a lot of restoration jobs. Polyester,acrylic,urethane, epoxies and more. And they are getting more amazing every year, but archectural epoxies and the epoxy for boat repair are designed to bond to surfaces different than sheetmetal. I know a collision repair guy that blows me away with what he can do. I haven't seen or read of epoxies being used for this purpose. There are epoxies that I'm sure would hold but then as I mentioned before you still have to deal with the solvents inherent to paint and why take chances? Unless you just want a challenge. Just as an example, when IMRON first came out everybody loved it and a great paint it still is. But I knew of a lot of good painters that had jobs go dull,lose their shine completely after a few months...it turned out to be a chemical reaction to a material that was in common use.

 

Hmmm. . .all good points to think about.

Thanks! If I decide to try it out at least, I'll post an update

 

Whichever way you go, good luck, and by all means HAVE FUN!...will look forward to update.