Rustproofing the frame (on car..)?

[4regt4]

You've given me lots to study.

I like the idea of a preventative that has penetrating abilities, as it will be difficult to do a thorough job with everything in place. But some of them may not be very long lasting, especially if exposed to petroleum products. Corrosion X, Permatex, and CRC 6026 look good. Some of the others mentioned don't seem widely available, like Dinitrol. Otherwise that would make the short list too.

If the frame were separated and stripped, POR 15 would be my first choice, as it could cover and seal the entire assembly. I've hit it with a hammer to demonstrate to people how tough it is, and it doesn't crack or chip - you can barely scuff it. However, applying it to an assembled car may end up sealing in pockets of moisture and corrosion. Hence my preference for a penetrant.

As usual, thanks one and all. You've been very helpful.

Hans.

[4regt4]

OK, I go a little OCD on stuff like this. Been reading up on the various products. A couple of things I've figured out:

1. The Permatex corrosion product is water based. It chemically alters the rust (turning it black), then dries with a coat of latex paint sealing the metal. Various tests I've run across seem to indicate that the paint sealant is quite durable. When dry it is very resistant to most solvents and cleaners, either water based or petroleum based.

2. Corrosion X is petroleum based. The basic Corrosion X is a competitor to WD-40, as it is a very thin penetrating oil. The product used as a corrosion inhibitor/preservative is actually Corrosion X HD, which is sort of a thickened version of the regular product. It leaves a film that doesn't wash off as easily as the regular product. Seems the resulting film is quite durable to most water based exposure, but not as good when exposed to solvents, etc. Like gasoline, paint thinner, etc.

I suppose that the Permatex would be longer lasting, however Corrosion X probably penetrates better into seams etc., such as pinch welds or other parts joined or even bolted together. I'm thinking that Permatex might actually trap moisture and corrosion in areas that It can't flow into. In a way it would be nice to layer them, however, I doubt Permatex would adhere to anything treated with a petroleum product.

Perhaps where there are welds or parts riveted or bolted together, a treatment with the thin Corrosion X directed at the joint followed up with a coating of Corrosion X HD over the general area may work best. But that's just conjecture.

Hans.

[richardcox_lotus]

I’ve been reading this thread with interest as I have a single rust spot on my galvanised chassis (subframe !) which I want to treat - it’s not the case that the whole thing needs recovering or painting. I’m not having the body taken off just for this spot !

So any recommendations for products is well received.

Thanks,
Richard

[4regt4]

I'm long on book learning and very short on actual experience. So take this with a grain of salt. Err.... No... Salt would be bad.

I think that bit of frame rust probably could be treated with almost any of the various products. But that suspension piece and it's bolt are also quite rusty. I think I'd use the penetrating oil products (Corrosion X HD) on them, and just for good measure spray a bit on the frame also.

The data sheets claim that Corrosion X products are safe on most rubber. I'm thinking of that suspension bushing, in case some gets slopped on there while doing that bolt.

CRC makes a zinc plating spray on product called "Zinc It". It's recommended for patching galvanized steel that has some of the coating missing. Check their website.

https://www.crcindustries.com/products/ ... s.html?p=1

Hans.

[Slowtus]

The notion of rustproofing the frame while said frame is attached to the car is a bit like having a shower while wearing clothes - it 'kinda' works...

[4regt4]

I don't disagree. I'm just going on the idea that anything is better than nothing. Especially in areas that are more readily exposed to the elements. Some of those areas also might be the easiest to treat.

Hans.