Surface rust

rosntom · 02-10-2005, 06:49 PM

The 356SC that I have had in storage (see above) does have surface rust on the pan and other areas under the car. It is not serious, but I would like to stop it. On my farm equipment, I have had excellent results using Ospho, iron oxide primer, and a quality finish coat. This would be pretty damned hard to do under the car. Do any of you have an easier solution to the problem?

id10t · 02-11-2005, 05:06 AM

Beauty is skin deep, ugly (and rust) goes right to tbe bone. There are some knowledgeable 356 folks in your area - I'd get with one of them to do the equivalent of a PPI so you know what you are dealing with.

Keith Perry · 02-11-2005, 03:40 PM

Hi. I've saved a few old trucks with ospho. I learned to use it on the metal parts of shrimp boats years ago. There's a 1948 Dodge pickup in my yard that I did 10 years ago with ospho, primer and paint, with no return of rust. I've also used POR15 on my 1975 Buick to stop the rust where prior applications of ospho didn't work. I like wire brushing, Marine Clean, Metal Etch, Primer and then POR15. I've had no failures doing that. Only my Porsche and a couple other old cars I have stay under cover, the rest are outside, in a very harsh environment, as I live on the beach. Check out the POR15 site. Oh, and do both sides of the metal you wish to protect. You do have a super car. Have fun!

rosntom · 02-12-2005, 05:10 AM

I appreciate the suggestions! You must live somewhere along the Gulf coast. I am not on it, but close enough to get the effects. I sometimes think how great it would be to live in a dry state where I wouldn't have to be dealing with it on a regular basis.

Argeo · 03-17-2005, 12:33 PM

Hi Keith,

Did you say you POR-15'd over veriprime and filler primer? I thought it had to be on the metal to work. I hope I am wrong, I just sprayed the Veri and Filler primer and realized I forgot to POR-15 the bottom of the rockers on my car. Be great if I could paint over.

Thanks,

David

Zeke · 03-18-2005, 07:01 AM

In my experience, once rust has been completely taken off, one can control the surface rust as you go. John Willhoit ( http://www.willhoitautorestoration.com/ ) leaves cars bare for weeks at a time. They wash them continually with a light phosphoric acid solution while they do repairs and metal bumping.

Once the car is ready for paint, wash it, neutralize it, dry it and paint it with your favorite system. I don't think he uses any POR 15 because his cars are rust free when painted. The theory behind POR (paint over rust) is that rust needs O2 to be active. A polyurethane based paint, which I think POR formulas are like or similar, will work its way into the pores and seal off any remaining active rust from the atmosphere.

What I'm concluding is. that if you were to media blast a part, painting it with POR products would be overkill. Just painting it with formidable products would be quite enough. Marginal parts need protection and sealing from O2.

My .02, that's all.

Argeo · 03-18-2005, 07:07 AM

Say there was rust that formed under the primer. Would Por over the primer do anything or waste of money?I would think it would seal it because the air supply has been cut off but I thought someone said it had to actually contact the metal to work.

Keith Perry · 03-18-2005, 01:19 PM

Hi. Argeo, your right. metal etch, POR15, primer and then surface paint. And for anyone interested, if your using Ospho, put a coat of primer on before the ospho completely dries, for the best adherence, then surface paint. I also agree with Zeke. I've found a 1958 Fiat 1200 Terissemo Velencia that seems to be just surface rust. The original owner passed it to a fellow who stripped the car to bare metal, put on a coat of spray can primer, and then the project was abandoned. It's been out from undercover for a year or so. I'll wash it down with Ospho and go from there.

Vandit · 10-14-2011, 01:11 PM

Sorry to be bumping an old thread, but my C2 has rust that is somewhat superficial on the inside of the front tub. I would like to treat this rust and then repaint the areas. Is Ospho the way to go? Would I simply brush it over the rusting areas that are adjacent to good paint? Or would I have to strip down the whole area?

Here's a pic of the affected area.

Please guide me on what would be the best approach.

Thank you.