Trailer painting

   / Trailer painting #31  
I did a open deck car trailer about 5yrs ago. I used a knotted wire cup brush or a needle scaler on every bit of it. Then rusty metal primer and black rustoleum sprayed through a HVLP gun. Looked great but used until I sold it at year 5.

For the underside use woolwax or fluid film once the paint is cured..about 30 days.
 
   / Trailer painting #32  
Surface prep is the most important thing when using poor-15. It is almost impossible to get trailer clean enough with wire brush to use por-15. It will start flaking off in the corners and then quickly progress over the rest of the trailer.
 
   / Trailer painting
  • Thread Starter
#33  
Surface prep is the most important thing when using poor-15. It is almost impossible to get trailer clean enough with wire brush to use por-15. It will start flaking off in the corners and then quickly progress over the rest of the trailer.
I keep hearing this. No only on the internet but in person as well.

I thought the thing was called "Paint Over Rust"???
 
   / Trailer painting #35  
So I finally purchased a trailer after 2+ years of on/off shopping. Its a 2015 24' 14k AMO bumper pull.

Trailer was overall pretty good shape. But I swear about every used trailer I saw of just about every brand.....its like they do minimal paint/prep work on the under side of the trailer. All the metal that can be "seen" going down the road...this trailer almost looks like the day it was made 8 years ago. But the cross members are pretty rusted. Nothing structural or rotten....just surface rusted and peeling paint.

So I pulled all the deck boards off and gonna paint. But that leaves the question.......how to proceed.

I have refinished a ton of old equipment and implements. And always had good luck with just a wire cup on an angle grinder.....knocking off all loose rust but not down to shiny steel. Then rustoleum primer....and either valspar or rustoleums "farm and implement" paint with their hardner. The stuff sold at TSC or rural king. I spray it with an air gun and its pretty cheap.....but even implements I painted 10 years ago still look real good and no rusting. But they also arent going down the road at 70mph getting water and road salt spray.

I have looked and stuff like por15 or similar are like $250/gallon and seems there are just as many people that say its junk as people who swear by it.

I know painting is all in the prep work....

I dont plan to grind the whole trailer. The outsides look good....I'll just do some touch up. Mainly concerned with everything on the underside. The 20-some 3" cross members, and the insides of the main channel frame that need attention.

Also open to better top-coat paints vs the rustoleum or valspar farm & implement stuff. Lots of "industrial" type coatings....or DTM type paints. Really want to find something readily available and not have to mail order.

Have also considered once I get the heavy stuff knocked off.....brushing on muratic acid then powerwashing. Muratic acid dissolves rust and leaves bare metal. And it wont effect the paint where the paint is still stuck good. (Makes rusted metal look like it has been sandblasted if you have never used muratic acid before). But that must be done outside or it will eat concrete.

So any of those of you that have stripped and re-done a trailer frame or similar.....what have you found that works the best? And what doesnt and not to waste time doing.

Given that I dont want to strip wiring, lighting, etc and the outside frame is fine....sandblasting is not really something I want to do.
I tell ya I've built a lot of trailers and rebuilt a few. The road is a destructive force from hell! If you use the trailer the road will strip the coating off. There was a time when I thought powder coating was the ultimate solution but even that proved to be a less than solution. The powder coating and epoxy type paints are almost - bullet proof - BUT!
Rocks and road debris will make small holes in the epoxy or powder coat finish where salts can get into the metal underneath and cause corrosion under the finish. This causes the finish to bubble up and makes the surface coating fall off eventually. Meanwhile the hidden corrosion is doing serious damage to the metal underneath.
I found I just coat it with a cheap overcoat to make it look good. In a few years that coating is stripped off by the road and I wash it with the pressure washer and reshoot it with the same color if need be. Usually the exposed metal has some surface oxidation, this is not a problem. If you shoot it with an epoxy or have it powder coated (which only works best when new) you can create bigger corrosion problems under that "tough" coating.
I've taken to shooting all the metal under the deck with a good ruberized underbody coating for cars like Barrier Bond. Then the customer facing surfaces get a good glossy rust resistant paint works the best.
 
   / Trailer painting
  • Thread Starter
#36  
I havent updated in awhile.

Trailer is almost done. Just buttoning up some wiring and lighting.

I ended up going with rustoleum farm and implement paint at TSC with hardner. Based on cost and having good luck with it in the past painting implements and bushhogs and such.
 
   / Trailer painting
  • Thread Starter
#37  
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   / Trailer painting #38  
So I finally purchased a trailer after 2+ years of on/off shopping. Its a 2015 24' 14k AMO bumper pull.

Trailer was overall pretty good shape. But I swear about every used trailer I saw of just about every brand.....its like they do minimal paint/prep work on the under side of the trailer. All the metal that can be "seen" going down the road...this trailer almost looks like the day it was made 8 years ago. But the cross members are pretty rusted. Nothing structural or rotten....just surface rusted and peeling paint.

So I pulled all the deck boards off and gonna paint. But that leaves the question.......how to proceed.

I have refinished a ton of old equipment and implements. And always had good luck with just a wire cup on an angle grinder.....knocking off all loose rust but not down to shiny steel. Then rustoleum primer....and either valspar or rustoleums "farm and implement" paint with their hardner. The stuff sold at TSC or rural king. I spray it with an air gun and its pretty cheap.....but even implements I painted 10 years ago still look real good and no rusting. But they also arent going down the road at 70mph getting water and road salt spray.

I have looked and stuff like por15 or similar are like $250/gallon and seems there are just as many people that say its junk as people who swear by it.

I know painting is all in the prep work....

I dont plan to grind the whole trailer. The outsides look good....I'll just do some touch up. Mainly concerned with everything on the underside. The 20-some 3" cross members, and the insides of the main channel frame that need attention.

Also open to better top-coat paints vs the rustoleum or valspar farm & implement stuff. Lots of "industrial" type coatings....or DTM type paints. Really want to find something readily available and not have to mail order.

Have also considered once I get the heavy stuff knocked off.....brushing on muratic acid then powerwashing. Muratic acid dissolves rust and leaves bare metal. And it wont effect the paint where the paint is still stuck good. (Makes rusted metal look like it has been sandblasted if you have never used muratic acid before). But that must be done outside or it will eat concrete.

So any of those of you that have stripped and re-done a trailer frame or similar.....what have you found that works the best? And what doesnt and not to waste time doing.

Given that I dont want to strip wiring, lighting, etc and the outside frame is fine....sandblasting is not really something I want to do.
I redid an old boat trailer down to bare metal and primed it the applied truck bed liner. I would do it again in a heartbeat.
 
   / Trailer painting #39  
Having been an Inspector in the Petrochemical Field for many years I have seen many types of Industrial Coatings. If you plan on keeping it for a long time and if it were ever to be exposed to salt then get it Sandblasted. Commercial Blast SP6.
Prime with Inorganic Zinc 3mils thick. Top coat with a Hi-Build Epoxy. Carboline Products were always excellent. Specialized equipment is needed. Do not power wire brush smooth as this destroys any anchor pattern on the steel for the coating.
Be sure and protect Wheel Bearings, Brakes etc when sand blasting. It looks in pretty good condition at present so you may get away with Brush off Blasting (SP 7 = NACE #4 specification) and a quality topcoat. If wiring is loose, put it inside plastic tubing. Do it once, do it right.
 
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   / Trailer painting #40  
Great review of all the methods to deal with rust. For the bottom of mower decks this is what I do. I haven't had good luck with heavy coats, which chip and rust underneath.

1. Wire brush and blow off rust.
2. Brush paint with OSPHO(water thin phosphoric acid).
3. Brush off dust and loose particles, and light wire brush any area of rust still showing.
4. Brush on another layer of OSPHO.
5. Wash surface with soap and water and dry.
6. Spray with spray on galvanize in a spray can.
7. Spray with Home Depot surface shield spray on surface protectant in a can. (It is like a light cosmoline and works if you want grass to fall off next year.)

Next year, wash or brush off grass crust. Respray areas where galvanize has worn off and recoat with surface shield. You end up using two $8. spray cans the first year. Not much after that. OSPHO is cheap at $48. gallon at ACE. It is very thin and goes a long way with a paint brush.

You can also just do two coats of OSPHO and 1 recoat when necessary. I would be tempted to do this on large surfaces like the bottom members of a trailer.

If you are painting or priming, especially after wire brushing, use prepaint cleaner from an auto body shop first to get off oils and silicone which make the paint fish eye.
 
 
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