Permatex Rust Treatment Issues

[Sundodger]

It seems this Permatex Rust Treatment (#81773) has created more rust than I originally had.

https://www.permatex.com/products/s...or-trim/permatex-rust-treatment/?locale=en_us

Background, this Dana 60 housing was in really good shape, minimal surface rust even. To prep it for rebuild I stripped it down then applied many many coats of this stuff. It does have its little idiosyncrasies, but overall went on well and everything was covered nicely.

After coating it with this stuff about 8 months ago, I got distracted with other things and left it in my dry shop under a cover until recently when I pulled the cover off to get back to work on it and found all this rust pushing though.
Now it has far more rust than when I got this out of the truck. I did make a few test runs with this stuff on scrap metal before using it, but I apparently didn’t let it sit long enough.

If I understand the chemistry right it should do a little moving of electrons around and that’s why I tested it on some scrap, but I expected it to eventually stabilize and encapsulate which it doesn’t look it did.

I am seriously considering wire wheeling all this stuff off and just painting it, but I am curious what other peoples experience good or bad is with this?

 

[CJM8515]

never used that stuff so i cant comment really. But I did clean up a very rusty rear axle for my old truck and sprayed it with rustoleum rust reformer. then top coated with rustoleum pro black. no more rust and never had an issue

 

[Slednut]

I've never seen that stuff.

I use epoxy primer, then spray it with a single stage matte black. If you don't have a spray set up I'd brush on POR-15, then paint it with whatever you want.

I don't know where you live in Washington but here on the east side of the mountains I can leave bare metal in my shop and it won't rust. If you have any chemicals like pool supplies it will make stuff rust.

 

[like2wheel]

Did it turn black when it dried?
That seems to be the key that it had the reaction to convert the rust.

I've had good luck with it as long as it had turned black, but I was under the impression that it needed to be topcoated.

 

[Sundodger]

The first coat it turned a dark purple to almost black, then after the second coat it was black (the color you see now in the photos where the rust hasn't broken though).

I was planning on top coating it before I installed it, I just didn't think I needed too with it sitting in my garage.

I am in western Washington, so the rainy side and bare metal will oxidize a bit in my shop, but if it can't handle my slightly humid shop then it will be crumbles of rust in short order bolted to the bottom of my truck.

 

[Dumber than lumber]

The Rust Reformer stuff mentioned recommends a topcoat of paint.
Alternatively spray galvanizing compound/paint might have been the product to use.
Good luck wth getting it resolved.

 

[like2wheel]

The first coat it turned a dark purple to almost black, then after the second coat it was black (the color you see now in the photos where the rust hasn't broken though).

I can't see the photos

 

[TonyG109]

Background, this Dana 60 housing was in really good shape, minimal surface rust even.

Strange as it seems, the issue may be that you didn't have enough rust to begin with. Rust converters require a fairly heavy layer of rust to "convert". They don't work on clean metal which it sounds like is your situation.

I was researching what to do with the bottom of a rusty RAM truck and finally found a fairly good set of instructions on one of the brands of rust converters. (I don't remember which one...) It was the only brand that clearly stated to only use on heavily rusted metal and it would not work on surface rust or clean metal.

 

[Sundodger]

I can't see the photos

Hmmm, hopefully others can. I will try to attach them instead of using imgur so hopefully all can see.

 

[Sundodger]

Strange as it seems, the issue may be that you didn't have enough rust to begin with. Rust converters require a fairly heavy layer of rust to "convert". They don't work on clean metal which it sounds like is your situation.

I was researching what to do with the bottom of a rusty RAM truck and finally found a fairly good set of instructions on one of the brands of rust converters. (I don't remember which one...) It was the only brand that clearly stated to only use on heavily rusted metal and it would not work on surface rust or clean metal.

Interesting, do you happen to remember what the brand of product was?

I thoroughly read the instructions, spec sheet, SDS sheet, etc. of the stuff I used, So I knew it was an acid converter (PH of 3.5), but I hadn't thought about the risk of what would happen if the acid didn't get fully neutralized. I mean, it did have some rust on it, But I assumed that after it had dissolved what rust was there, it would make a bit more and dissolve it (etch the surface) until the was no excess reagent. It seems that is not the case.

It's tag line was also misleading, at least the last part.

"Kills old rust – prevents new rust"

 

[TonyG109]

Interesting, do you happen to remember what the brand of product was?

I thoroughly read the instructions, spec sheet, SDS sheet, etc. of the stuff I used, So I knew it was an acid converter (PH of 3.5), but I hadn't thought about the risk of what would happen if the acid didn't get fully neutralized. I mean, it did have some rust on it, But I assumed that after it had dissolved what rust was there, it would make a bit more and dissolve it (etch the surface) until the was no excess reagent. It seems that is not the case.

It's tag line was also misleading, at least the last part.

"Kills old rust – prevents new rust"

I can't find exactly where I read this but the below link to the TheRustStore.com FAQ has the following about their rust converter product that I assume uses similar chemistry to other rust converters :

Can I apply Rust Converter over non-rusted or painted surfaces? Yes, Rust Converter will adhere to non-rusted or painted surfaces but it does not provide any additional rust prevention when used on these surfaces.

https://www.theruststore.com/Rust-Converter-FAQs-W48.aspx

This is what steered me away from using a rust converter and toward a different product for my particular situation.

 

[Sundodger]

Thank you

Luckily this stuff and the rust is coming off pretty easily with a wire wheel other than the nooks and crannies of course.

What's really surprising is the rust that was pushing through the coating seems to be purely surface. I am used to when rust is erupting though a surface, there is a lot more ugliness below and there isn't here. Maybe it wouldn't have been as bad as I thought, or maybe it would have been pitting and crumbling away in 6 months.

 

[mikegt4]

I have never had any luck with Rust Converter products, they don't seem to be anything but a short term band-aid solution.