Rust and Flaking Paint

[dlajoie]

Upon inspecting the underneath of our 2003 2720SL, I was surprised to see the extent of rust and flaking paint on underfloor frame crossmembers and torsion bars. We live 30 miles from the ocean but bought our TM on Cape Cod. I know salt air could be a culprit but suspect poor quality paint or preparation at the factory is more likely. Are there any out there with similar rust or an opinion on how to deal with it. I'm thinking I have to sand, paint, and/or use spray undercoating - looks like quite a job.

I have the same problem. I live right on the coast and mine is rusting pretty good also. What I have done was bought me a little wire brush and some Spray paint with rust inhibitor and I just keep up with it. I guess being in the Navy I'm used to this concept. haha

There's some stuff called "Rust Doctor" that will stop the rust and then you can paint over it. http://www.therustdoctor.com/ I used another brand that worked well, but I can't remember the name of it. You have to get the worst part (read loose) of the rust off and then you put the rust killer on. It will turn black and when it dries you paint right over it. My frame looks new now. I used "Rustoleum" paint over the rust killer.

I too live on the coast and have already had to repaint the LP tanks and the bed supports. They need it again. The tounge, jacks and frame are next. I am going to try the spray on bed liner stuff from NAPA on the tounge and frame.

[Bill]

Live2shopnc -

Hey, that should be a great idea! Let us know how it works. I've tried the rust converter stuff, with less than sterling results.

Bill

any outcome on all of this. I was under mine the other day adjusting the brakes and noticed the torsion bars were awful. got a wire brush after them and cleaned off all the flaked areas (which is basically the entire bars under the frame)
would just painting them at this point be good enough. I wonder if the stress on them might have caused them to rust / flake like that.
any suggestions??
Thanks

[Wavery]

I have painted a few trailer frames in my time. I would recommend NOT using aerosol spray cans. They are 90% solvents and thinners that evaporate and 10% paint.

I recommend using an airless sprayer. You can lay down a much thicker layer of paint. Although, I would also recommend laying down one thin coat first, allow to dry for an hour, then lay down a finish coat.

Aerosol paint runs very easily, even though it is a thinner coat. When you spray with an airless sprayer, you use very little (if any) thinner and you can get twice as much paint on without running.

Care must still be taken to avoid runs. 3 thin coats with an airless should look great and last for years. All of the work is in the preparation, don't waist all that hard work by using spray cans of paint.

You can buy Rustoleum paint by the quart or gallon.

The problem with bed-liner paint is that you can get pockets of moisture and corrosion and not even know it because the stuff makes a "Shell" over the area that is is covering. This shell could have nothing under it (over time) and you wouldn't even know it until the frame actually crumbled. It's far better to have the corroding metal expose itself by having the paint give way.

[ShrimpBurrito]

Using a brush, I painted the A-frame (tongue) on my TM with 2 or 3 coats of black Rustoleum. The rock chips and associated rust spots were back in less than a year. I think it's more a problem of abrasive road debris.

Dave

[Wavery]

Originally Posted by ShrimpBurrito

Using a brush, I painted the A-frame (tongue) on my TM with 2 or 3 coats of black Rustoleum. The rock chips and associated rust spots were back in less than a year. I think it's more a problem of abrasive road debris.

Dave

Using a brush on an exterior surface has a lot of disadvantages. For one thing, the uneven surface from the brush strokes leave places for water and dirt to accumulate. This causes bacterial growth that attacks the paint and the under lying surface.

When you spray the surface, you end up with a coating that is less likely to trap particles and will reflect the harmful UV rays from the Sun. A rough surface will absorb UV and break-down much faster. It's not all about esthetic's.

Before you paint you must be really sure that all rust is gone. I used cheapo harbor freight sandblaster. (VERY IMPORTANT -- USE EYE AND BREATH PROTECTION!)
After that I just brushed it on, primer first and then a layer of rustoleum.
It's held up two years and miles of towing.