Rust Conversion/Protection

[SEMott]

I have a large house trailer that has a sheet metal roof that has never been coated before. For the past 20 years the trailer was covered but is now exposed (now a camp in a saltwater enviroment). I've looked into some products but you can't alway believe what you read so I am looking for some advice. I was looking into some of these products:
-Rust Bullet
-Rust Converter by Duluth Trading
-Rust Doctor
-Zero Rust
-Por 15

Any thoughts on these or any other products?



Stephen E. Motichek
Project Consulting Services, Inc.

 

[rhodie]

My employer makes a version of this class of product.

It resembles a very acidic topcoat that changes the reaction of disimilar metals (oxidation) into a cationic and anionic reaction. It will indeed stop the rusting, and even convert that rust into the coating itself.

I am not familiar with some of the products you listed above, but I'd be willing to bet all of them produce a black colored film when dry. That color is a result the carbonic byproduct of the reaction. (Black probably isn't the best color to be painting a roof, but I could be mistaken in your application...)

I will tell you this- I've never heard of a customer that has ever purchased this class of product from my company ever being extremely thrilled with the result it offered over a similar corrosion inhibiting primer and white (for solar shielding) alykd based topcoat system.

It doesn't sound like you have a large amount of rust to deal with just yet; why not just prime and paint it? If has rusted, I'd just as well be prepared to remove it, rather than trying this exotic solution for such a large area as a roof.

Also- you said the roof was previously uncoated. Does this extend to the galvaniziation of the steel? If the steel was previously galvanized, it could impact you primer selection greatly.

Lastly- Unless you are deadset on an oilbased system, I'd prime and then topcoat with a latex based elastomeric product, which is a cheaper, easier to clean, better for the environment, and overall superior roof coating.

Let me know which direction you go with this project! Hope this helps!


Rhodie

 

[SEMott]

Hey Rhodie,

Thanks for the response. Your right, just about all of products I listed turn into a black film. Most of them sell for about $35-50/gal. and require a topcoat due to the exposure to the elements. The one Rust-Bullet is silvery/gray when applied, stays that way and doesn't need a topcoat but it is in the range of a $100/gal.

The whole roof is rusted pretty bad but it doesn't have any holes or pits...yet. Can't tell if it was galvanized or not. We figure we'll have to replace it some time or more than likely build a roof over it and create some additional rooms.

The roof looks like something needs to be done pretty soon. We're just looking buy some time with a coating versus building a covering.




Stephen E. Motichek
Project Consulting Services, Inc.