Bondo, will it hold up.

I just picked up a 72 Dart. It has a pretty new paint job and looks like a great car. On close inspection both rear lower rear quarters, behind the back tires are pretty thick in bondo and there is evidence of some interesting body repair (sheet metal screws) looking from the backside of the quarter. Both corners by the rear window/trunk are heavily molded with filler as well. But, everything feels solid.

The car looks good, the paint is solid, no visible rust, and I'm in central Texas so that helps. I plan to use this car as a daily driver, 50 miles of highway driving a day, parking outside.

Will the body work hold up? Can I expect the car to stay looking decent for quite a few years or will these body repairs come back to haunt me pretty soon? I have no experience with heavily rust repaired vehicles.

It's hard to make sweeping generalities about filler longevity vs. thickness. There are just too many variables. However, it has been my experience that if the panel flexes at all, thick filler will eventually fail. A prime example are the 'C' pillars. Eventually the filler will crack and fail. The body just flexes too much at this point. As to the quarters, what is pretty thick? I've seen 1/2" of filler on quarters that survived. You'll just have to see.

flip of the coin.

If it gets wet from the backside the filler can fail that way as well.

Way too many variables and unknowns to say.

A toss up, what I was afraid of. I have another Dart that is rust free and just a little bondo where the roof seam is, like they all have, but the paint job on it isn't as nice and its a little rougher interior wise so I'm trying to decide which one to keep.

The instant gratification that might fall apart or the one that's still a bit of a project.

Anytime filler is more than 3/8" thick you're asking for trouble. Based on your description I suspect the previous owner took the easy way out and just slapped on filler instead of replacing the metal, which would have been the correct way to repair those panels.

As others have said, flip a coin. However if it's really thick... it will fail sooner rather than later.

Just drive it and don't worry about it. If it starts looking bad, take a couple of weekends and fix it the right way.

Depends a lot on how the repair area was prepped and sealed. Done right with the right products, filler can last forever. Done poorly, as in cheap bondo slapped directly over rust or unsealed metal joints and you will see rust bubbling and rust juices pushing through in a year or two.

I've used sheet metal screws to hold my sheet metal in place while I do tack welds, but I always remove them and fill in the holes. If he left the sheet metal screws in place that tells me he didn't weld anything and piled the filler on heavy enough to hide the screw heads. These old cars flex a lot in that rear window/trunk area. I see a lot of mopars with cracking filler where guys tried to blend over the seam between the panel that goes in front of the trunk where it meets the quarter panel.

I think you should sell the car now while it still looks good. If you keep it, it'll look good for a year or two, then you'll start seeing some cracking around your trunk/quarter window area and some bubbling in your quarter panels behind and around the rear tires. 5 years from now you will be seriously unhappy with it.

Being from NY and seeing and owning my share of bondo buckets my experience is, if you garage keep it and fair weather drive it you may be okay. If you keep the car in rain, it will bubble, crack and then start to fall out.

If you are keeping one of them, I would keep the solid car and sell this one. Replacing a ratty interior is cheaper and easier than good body work, I would also be afraid of unseen stuff hiding in the bondo car.

Keep the solid car, sell the sheetmetal screwed one now while it still looks okay.
If it doesn't get wet it may last awhile but those screws are not a good thing. They are bound to start moving a bit with vibration and driving over bumps etc. over time. Plus you will always feel like you are driving a bondoed up junker.

I'd be more inclined to keep the car with worse paint but more solid body panels...but based on other variables like suspension upgrades and the motor/trans/rearend it's still hard to say.

I think I'm going to go with my gut and sell this pretty car with issues and keep the solid car. if it was going to sit in the garage and get driven on nice weekends I would probably do it differently, but I am truly looking for a daily driver and a paint job is cheaper than bad body work repair. I do have to say the guy was good with bondo, you can't see the screw heads on the front side anywhere. I will take some pics soon, I know it would have made this post a little better.

Thanks everyone for your opinions, my gut was already there, but sometimes the voice of a community makes you feel better about it.


Now lets see how good you are, which one is which.

I'd say the black one is the Bondo queen.

If they didn't kill the rust behind the bondo the cancer will continue to grow and push that stuff off the car.

I see a green and a blue one

blue bondo bomb

winner winner. blue one is a lesson in bondo molding.

Green one really isn't bad, its just too dark of a green and it wasn't body worked so lots of waves down the sides and it wasn't jammed so the original medium green is inside everything and whoever painted it didn't get the underside of the body so if you lay under the car its primer with a bit of surface rust around the edges, but you can also see its all original metal too.

I know I'll just sell them both and see if i can find a new 2016 sitting on a lot still.

I have a 440 powered 73 Dart 4 dr. Assembled in 1999. I removed all the body through-holes and bondoed the holes for a slick body look. I am not a body guy and did not get a smooth surface that really showed after I had it painted. Any rust I found (very little)I cleaned to shiny metal and also bondoed.
The body has not cracked or separated as of today. I am in North Texas the hot sun is the biggest paint and body killer around here. It mostly garaged and not a daily driver.

I would put all the good stuff on the car you keep of course. The green car would look better with the rallye rims IMO.

Keep em both! I would love to have either one. Im currently cloning a 73 swinger into a 72...my first car was a 72.

I once rebuilt the last 3-4" of a fender with plastic body filler. This was a front door and the area on the fender right ahead of the door was pretty bad. When I hit it with a grinder it got worse. So I built it myself. It looked pretty good. O drove it for six years after that and there was no indication that it was coming apart.

R.

That's green? Boy, my monitor is really off. It looks like black.

It's a DARK green. The previous owner said it was some BMW color, I think. I thought it would grow on me more, but speaking the jams and interior is still the F3 medium green and that dark green even is a little more blue than the mopar greens, it's just off.

One of these days I will probably get it repainted and do it F7 dark green or screw it all and paint it white.

^ oh man, i think the f3 medium green is awesome. bummer it's a weird dark green now.

we once built the bottom quarters of a 69 chevelle by taking duct tape and defining the outside of the quarters, then pouring two part expanding foam into the cavity between the inner and outer quarters. after it set up, a "cheese grater" file skimmed it down to shape because the foam stretched the duct tape outward. after skimming the foam, a coat of bondo, sand, and paint. looked great ! mixed up a bunch of left over paint cans to come up with a reddish-orange color, and a fast sale it was ! it lasted three winters until the new owner managed to crash it. upon viewing it in the junkyard, the quarters still looked as good [] as the day they were made !

[and to think an old guy once told us at the auction : "cars with bondo aren't safe !"]