Rust Spots Questions

[A4orce84]

Hello Everyone,

As I am getting close to solving my coolant gauge issue (hopefully), I'm moving down the TODO list on other items I need to address on my B6. A few months ago, I installed some updated S4 Door blades on my car. I saw the following on the bottom of the driver's side door:

Pictures:



As you can tell from the first picture, there is a circular rust spot forming. Thankfully those were the only rust spots on the whole car, the other 3 doors are fine. I bought the car originally from the Chicago area, and drove it down to TX back in 2009. So the winter weathers (aka salt) should no longer be an issue, but I wanted to ask a few questions since these spots were hiding behind my old USP door blades originally.......

Questions:
1. Should I be pro-active on this small rust spot?
2. Will it still pose a threat in the future (ie spreading up to the main door area)?
3. If I do need to stop it, what is the best way to treat it and prevent it from getting worse?

Thanks in advance everyone! All your time and help is greatly appreciated! =)

Thanks,
Asif Ahmad

[claudiovagkraft]

Never let rust "go", it just grows and grows and grows. It's hard to say when it will become a problem, but it will. So it's not and "if" but a "when". Dealing with it now will be much lest costly than when it starts to creep up the door from under the door blade. Ask yourself what the plans for your car are and how long you plan to keep it. That should determine your course of action. But seeing that you're in Texas, deal with it now when it's easy and cheap and you'll probably never have to deal with it again.

[kifac]

Never let rust "go", it just grows and grows and grows. It's hard to say when it will become a problem, but it will. So it's not and "if" but a "when". Dealing with it now will be much lest costly than when it starts to creep up the door from under the door blade. Ask yourself what the plans for your car are and how long you plan to keep it. That should determine your course of action. But seeing that you're in Texas, deal with it now when it's easy and cheap and you'll probably never have to deal with it again.

What about us living in Toronto LOL

[Kevin C]

My fix... Mask the good paint. Spot sand blast, then acid etch and prime or hit it with a quality self etching primer. Some color to hide the fix. I know it's hidden, I'm like that.

[claudiovagkraft]

What about us living in Toronto LOL

We need to get on that shit ASAP!!! And follow up with rust proofing, and wash your car regularly in the winter

[diagnosticator]

There are rust converter products that change the rust, iron oxide, into Iron phosphate, not rust. One good spray on converter is loctite Extend, it converts rust into iron phosphate, a hard black material that won't continue to form rust, and forms a good base for primer and paint

https://www.google.com/search?q=loct...w=1536&bih=764

Extend is available as a spray on or as a water based brush on.

[A4orce84]

Sir nosticator of Diagnostic:

Thanks for the info! Have you used this or similar products in the past?

Thanks,
Asif

[Kevin C]

POR15 is another coating and in my experience one of the best. The latex based converters (like the loctite) work reasonably well but must be covered over to last. Mechanically removing rust is the best solution. Often time, there will be layers that converters can not get to. I have even used converters after sand blasting. Watch for any breakthrough to the inside of the door skin, that will always come back unless fully prepped.

[eljay]

Another vote for POR-15. But get rid of as much rust as possible first. Keep in mind that any of these products prevent rust from forming where they are applied. If you allow a place where moisture can get in, it will rust again. In other words, if the rust is coming from the other side, covering up one side with POR-15 will not stop rust. The product needs to encapsulate (another rust converter product, btw!) the fix area or it will come back again.

[diagnosticator]

Sir nosticator of Diagnostic:

Thanks for the info! Have you used this or similar products in the past?

Thanks,
Asif

Yes I have used the Loctite Extend rust converter products, works really good. Extend changes the rust to iron phosphate completely to the base metal, not just a coating over the rust.