Painting an aluminum/galvanized trailer

[Donziweasel]

My 18 arrived today, which is sweet. I am not to big on the aesthetics of the trailer. It is aluminum with a galvanized tongue. What would I have to do to paint it? Prep work? Type of primer? Type of paint? I have some nice paint guns and a sweet compressor.

[MOP]

I have had ery good luck painting "aged" galvanized stuff, Aluminum requires prep. If you have a local shop that does a lot of aluminum work they should have the caustic wash, it does a very good job followed up with zinc chromate primer then your choice of a good paint. I used the wash I got from my local welding shop before I installed my new tank.

Phil

[Donziweasel]

Thanks Phil, I will look into the wash. :)

[Morgan's Cloud]

I'm not sure if it applies in your case , but when I repainted my entire lower unit in February after having it blasted I used a catalyzed two part etching primer first made especially for aluminium alloys.

I wasn't taking any chances with single stage zinc chromate.

[Donziweasel]

Thanks for the tip. I think to paint aluminum you have to have at least an acid etching primer, but I am still trying to figure it out.

[Scott Pearson]

You MUST coat aluminum within 8 hours after sanding with whatever product you choose also you MUST coat the areas that are aluminum to aluminum or you WILL get galvanic corrosion.

[joseph m. hahnl]

My 02. The coat of oxidation is what protects the aluminum from further corrosion.
Salt, "which at, 7000' in the clouds isn't really an issue" being abrasive washes the film or shell of corrosion off . It reforms the oxidation and goes on and on until there nothing left. .So in order to paint it, you have to get rid of the shell. Sanding's going to be a PITA :mad:. An acid etch with a sponge and brush would be much easier.:shocking:

[Donziweasel]

Thanks Joseph. Looking into the acid wash.

[Tidbart]

Alodine. Cheap and easy to use prep for aluminum.
Good quality epoxy primer.
A quality finish paint.
Then I would put some clear on top

B

[Scott Pearson]

I would NOT relay on a chemical only adhesion.... Trust me, you need both machanical and chemical.

But what do I know.... I only work for the biggest coatings manufacture in the world.

[Donziweasel]

Scott, how do I get mechanical adhesion? Thanks.

[Scott Pearson]

Sanding would be one way and the easiest way.

[Scott Pearson]

Also, if you do go with a type of liquid acid wash you have better know what you are doing. If you don't use these types of systems correctly the paint could delaminate much easier.

[Donziweasel]

Gotcha. Thanks for the help.

[Greg Guimond]

I am out of my element here but I figured I would just throw this in. I spoke to a gentleman that had purchased a go fast with a very high end West Coast trailer. The left coast folks only build with steel as they are all freshwater boaters for the most part. This guy was going to dunk it on occasion in salt and wanted to preserve it because it was truly custom to the boat. He found some company that basically was able to dismantle the trailer and "dip" the entire thing into a vat of something to strip it. Then they dipped it into another vat of something else which evidently galvanized the entire frame to a very high standard.

First I have ever heard of this but sounded kind of efficient.

[Scott Pearson]

There is a guy here on the East coast that will hot dip galvanize and powder coat a steel trailer. I think its about $1200.

[Greg Guimond]

Interesting Scott. Do you have the name of the company? That is not terribly expensive. As to the powder coating for salt water would that hold up bonded to galvanized steel?

[Ghost]

Interesting Scott. Do you have the name of the company? That is not terribly expensive. As to the powder coating for salt water would that hold up bonded to galvanized steel?

i had a myco that I believe was factory paint-over-galvanized steel that probably stood up to south florida salt for 15 to 20 years. (Which might sound okay but doesn't appeal to me. Faced with trying to make it look decent again, replaced it with a galvanized trailer which should last for 30 years at least. Maybe 50 plus. Not sexy to look at but the look should never get degraded much.)

[Scott Pearson]

Bill from Performance Trailer in Lake George has a guy who does it. Not sure who he is just know he does that sort of work.

[Donziweasel]

I think there is a guy about 90 miles from me who does the dip.

[Donziweasel]

What about bead blasting? Worth looking at?

[joseph m. hahnl]

What about bead blasting? Worth looking at? That by far is the best method:p. No sanding no chemicals:D

[Greg Guimond]

I have had several items done with a high end powder coater and if they had direct contact with salt the powder would give way in spots over a couple of years. The shop even said that would be the case. The guy I talked to who did the custom trailer dip for cleansing and then a second dip to galvanize the steel left it galvanized with no further application of either paint or powder coat. It sounds kind of interesting but I'm sure in addition to a 40' long tank there is a lot of science behind it and you have to find a highly competent shop.