Best paint for somewhat rusty trailer

I am redoing my 35 year old utility trailer. It has a very heavy duty frame that is somewhat rusted. I'd like to paint it with a rust preventative paint. My experience with Rust-Oleum is not all that great. Basically even with the surface is well prepared (e.g. sanded/degreased) whenever the paint is scratched or dinged rust seems to creep under the paint. I guess it is not adhering as well as I'd like. My hope is that with the wide range of experience in this forum that I can get some suggestions for a better product.

I have had luck with these two. They are not paint, they are prep for the paint. Jim
Eastwood

VHT

I have had very good results with most any implement paint on faded and rusty surfaces. I pressure wash with just cold water first, Its easy and it works well. I just spray paint Without priming using qts or gallons.

take it apart and then take it to be hot dip galvanized.

When you see metal rusting you are just seeing what is bleeding through the surface. If you would scrape the paint off you would see the rusted area is much larger, the metal is rusting through the paint. It would be best to take a sander and some coarse sandpaper and sand it down to the metal in as many places as you can. Then prime it and paint it. The regular line of Rust-Oleum paint isn't so great but I've have very good luck with there Farm and Implement paint. I painted a tractor with it more than 10 years ago and it's holding up better than Dupont Nason automotive paint.

If you want paint not to creep out under the paint where there is a scratch use an epoxy primer. It will keep the rust isolated to the scratch.

I have had good luck with a product called "Rust Bullet". Pricey but the industrial one has held up for fifteen years on a trailer of mine, The trailer does not see any foul weather use tho.

(quoted from post at 22:03:11 03/15/21)
take it apart and then take it to be hot dip galvanized.

Click to expand...

Could you provide the name and address of a business that could galvanize a trailer?

I've had good luck using Gemplers rust converter. You can spray it, brush it or roll it on the rust and it chemically changes the rust and makes it inert. The surface turns black and paint sticks to it pretty well. I've got some things I used it on that were very rusty and now 5 plus years later the paint still looks very good.

Paint is a hard skin to seal the surface of steel from the rest of the world. If the paint gets scratched, the seal is gone.

Rust is an active process, requiring the steel, plus moisture & oxygen to work. If any rust is still present while refinishing, this rust will continue to fester and eventually blister the paint from underneith. Scratch the paint on a perfectly painted piece of steel, and it will begin to rust.

Trailer life is rough. Sliding cargo, chains, rocks thrown up from the pull vehicle, all contribute to breaching the seal on the paint coating. Using a trailer in a salty enviroment (winter roads or near the coast) adds another layer of defeat to the trailer.

Thicker paint (heavy, or multi coats) does add thicker layer that must be penetrated by an impact, so there is some value there.

A coating that is flexible is of great help, but has other issues.

The paint on your car lasts longer because it doesn't see the abuse you put your trailer thru.

Occasional prep & repaint is about your only economical option. My equipment trailer lives outside. It gets repainted about every 5 years, and doesn't get used in the winter.

My experiences......

(quoted from post at 09:14:32 03/16/21)

(quoted from post at 22:03:11 03/15/21)
take it apart and then take it to be hot dip galvanized.

Click to expand...

Could you provide the name and address of a business that could galvanize a trailer?

Click to expand...

We use their Tampa area location.
Plug in your zipcode to see nearest to you.
https://www.valmontcoatings.com/locations

is

Also South Atlantic Galvanizing but they are only in the southeast.

I'd think you would have to sand, grind, or sandblast off the rust if you are trying to get back to perfect. Then if you are going black, get some of that truck bed coating and underneath try some undercoat. I got a couple spray cans of rustoleum undercoat today and I'm going to try on a couple things.

I will add some things to Petes list.
First: it is true that rust needs moisture, but that doesn't mean rain. Rust will suck moisture out of humid air.

second, though it is true that thicker paint will help protect from chipping, it is no protection at all from the rust underneath that you paint over, so you must remove all of the rust. As others have said sand the rust off. The best way that I have found that is with a flap wheel in a 4.5 inch grinder.

Third: After removing the rust convert what you haven't gotten with a rust converter. There are many brands, but they all have phosphoric acid as the active ingredient.

Fourth; As Stephen said for adhesion prime with epoxy primer.