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How bad can this rust spot on my door get?

Had someone somehow leave a dent about half a foot across at a weird angle just above my rear driver-side door handle earlier this year. The paint was only slightly broken at the time so I figured a paintless dent repair would be fine, and I found someone willing to give me an approximate price quote by just sending my pictures of the damage.

That got rid of the dent, but the broken paint gradually got worse over the months and now there’s a big rust spot there since the cracked paint just peeled off. It’s a bit of a hassle for me because it seems most bodyshops aren’t even willing to give a ballpark estimate with clear pictures alone, and require that I take my car in person.

I’m worried about what to expect about pricing to completely clear the rust and match the paint, and how bad it could get if I let it go. If it’s some ridiculous cost like nearly $1,000 or more(my insurance deductible is already $1,000, if that matters), I’m tempted to just scrape off the rust myself and use some touchup paint to hide it as best I can. I’d rather not continue doing nothing about this, but if I did, could it get so bad as to eventually rust out a large portion of the door?

Any advice appreciated!

That should not surprise you at all.

A dealer can sell you a small bottle of touch up paint by looking at your VIN. Just sand it lightly and cover it with the paint and watch it for a while.

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When bare steel is exposed to the environment, it rusts.

So you can remove the dent from the steel, but if you don’t protect the steel, it rusts.

My daughter has a scratch on her car door down to bare metal and it’s rusting.

I showed her the paint code for her vehicle so she could get touch-up paint so I could repair it.

But, I guess the ole man knows nothing and she hasn’t acted.

So when next spring rolls around, and there’s a hole in the door, that’s when she’ll ask me to fix it.

Tester

You could paint that yourself. You’d have to sand the area down, maybe a thin layer of filler, sand again then paint. If you want it to look invisible, go to a body shop. Shouldn’t cost too much for that small spot.

That small spot?

Maybe $800.00.

Tester

Lol, I never have body work done.

I use to do bodywork!

Tester

For something like that just do it yourself. I’ve got a small pea size spot I have to do this fall too. You need to completely remove the rust though before doing anything or it will just come back. Something like Naval Jelly over a couple days will dissolve the rust. Then just carefully scrape those loose parts off and use a bottle of touch up paint with the brush. Primer first then the color and keep it within the lines and enough coats to match the surface. You could also use the clear in the bottle for the final coat or two. If you really want, you can blend it all in with 2000 or so grit wet or dry sandpaper, then use rubbing compound to polish it to match. You should have all this stuff on hand anyway for other nicks.

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People need to remember, the rust you see is only about 30% of the rust that’s actually there.

Tester

Not if you do it right. You’ll need to sand it down to the metal, clean, prime, paint, and if it had clearcoat, do that too, then rub it out and polish it wit polishing compound.

I’m sure there’s a good video on the internet on how to do automotive paint, or if you prefer books like I do your local bookstore should have a book on the subject.

Normally I’d agree, but in this case it appears to be surface rust from adhesion failure of the paint that Paintless Dent Repair did. You get what you pay for. Although I could be wrong on that.

Making judgements from a picture is always risky. That’s why no reputable shop will do so without actually seeing the vehicle. NOTE: I added these comments for the OP’s benefit.

If you don’t have the time/$ to fix it cosmetically, you should still remove the rust the best you can per the ideas above, then paint the bare metal with a couple of coats of primer or something, even just clear nail polish, just enough to protect it from rusting more.

If it’s too expensive, go to a junk yard and get a replacement door. Might take a while to find the right one / color, but it’ll be cheaper.

When you first spot rust remember this – “A stitch in time saves nine”.

Just an FYI- normal primer will not inhibit rust. I’ve known guys that shot the primer and stopped, thinking they could wait indefinitely to do the color painting. It was only marginally better than bare metal. Nothing like having to start over and remove all the primer and rust back to bare metal…

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Yup, rust is like cancer and unless it is all removed it just bubbles back. Sanding is sometimes a problem though because it will cover the rust instead of removing it. A chemical acid cleaner is best or sand blasting first. Primer is porous and not intended to protect metal. It is meant to provide a base for paint and will let the moisture through to the metal. Shop grade primer though will stop the moisture but is not something normally used by DIY folks.

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That’s generally true. The belief that it will comes from many years ago when primers contained zinc. Zinc as a primer additive was banned decades ago. Modern primers do a poor job of preventing rust.

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Primer is meant to hold the top coat on the metal, not act as a barrier to the environment. I would mask off an area around the rust spot that you are willing to repaint. Then sand off the rust, clean and dry the spot, and primer it. You might want to tape some paper to the existing masking tape before priming. That will keep the primer off the rest of the car. You want a thin coat. Start on the paper and move at a steady rate across the area. If you use gray primer, you want just enough primer that the entire area is gray and no more. Primer isn’t strong and the more you use, the worse the adhesion. Let it dry as long as the instructions say, sand it smooth, clean it, and put the top coat on. After the top coat dries, pull all the masking off and sand it smooth. It won’t look professional, but it will be good enough.