Bodywork Spot Rust

6 Sep 2007
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United Kingdom
Bought a 1972 classic Fiat 500 a couple of years ago.

Stripped it down, got the whole car media blasted, and a coat of acid etch primer on top, with the intention of putting another couple of coats of build primer on before getting it painted.

Life being life, a family member got really ill and needed 24hr care for the next couple of years. So the Fiat 500 project was left to sit in the garage, in nothing but it's etch primer for a couple of years.

I'm now in a position to finish the project. I've had a look at the bodywork, and the primer has lots of small rust spots all over. I done quick trial sanding back to the metal, but I've noticed very feint small black/grey dots which I presume are the remnants of the rust. How deep will these little roots go? Should I treat the bare metal with Jenolite before spraying the new etch prime, or should I have it media blasted again?

Thanks in advance for your help.

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personally if it were me id have it blasted and start again if sanding it didnt remove it, its hard to advise without seeing it.
Hopefully the spots are just staining after removing the surface rust. Especially if its not rough under your finger?

If you get it blasted again, I'm guessing there wont be much of the little thing left?

Use a high build two pack primer (with hardener) and on the plus side, you have no large panels to deal with. Are you painting yourself or getting someone to refinish it for you?
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Thanks for your advise lads.

Mursal, I think the marks are just staining. The surface of the metal is as smooth as glass. I was just worried that it wasn't exactly the same colour as the surrounding 'clean' metal. You have to look close to see it though. Maybe I'm just being too fussy. I will be doing the primers myself. But will leave the paint to a paint shop with an oven. Would I need repirator if it was to use the high build two pack?

You're right that there might be nothing of the wee car left if I have it blasted again! As you say, it's not a huge area to sand by hand.

ch427, Thanks for the link to practical classics. Looks like a good product. Thankfully my project isn't anywhere near the condition of the photos in the article. My problem is more like little pin head sized spot of rust showing through the acid primer. After a few seconds of sanding the rust spots are gone leaving a very feint dark stain.

What do you think of my action plan?

1. Sand away existing etch primer & rust.
2. Treat bare metal with Jenolite rust treatment liquid.
3. Acid etch Prime.
4. 1st coat Build Primer - Sand - 2nd coat Build Primer
5. Send to paintshop

Thanks for your help.
Yes a respirator and plenty of fresh air in the area you re working. I think they recommend a pressure mask from the compressor air supply.

Plan of attack looks good, just double check if you need to sand after the rust killer, as some dry very shiny and may not take the primer properly without sanding.

We sometimes like to brush on the primer into the little concave corners (but don't tell anyone). A long stick taped to the brush handle helps. This takes the pressure off the spray gun, allowing you to concentrate on the flats.
Thanks for the tips Mursal.

Nothing quite like good advice from someone who knows what they're doing.

Let you know how it goes.

I realise a few months have passed since post was shared, so wandering if you have found the best solution to combating the rust spots or if the car is still posing a challenge. If you are still working on your car here is my contribution to consider - Many classic car enthusiasts use a product called Dinitrol to treat rust spots. You can visit the Dinitrol website for phone number and details of which product will work best. I am sure if you phoned they will offer good advice - worth a try - but good reviews on other auto forum sites.

Good Luck![http://www.xxxx
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