Any metalurgy experts out there?

[Bizywk]

Has anyone ever heard of painting a galvanized trailer?

Of course there are ways to prep the zinc on the galvanized surface to make paint stick giving the best of both worlds - a clean higher end look while retaining greater rust protection, but being able to do something doesn't mean its a good idea. There doesn't seem to be much on the topic out there.

 

[Trannyguy]

I am definitely not any kind of expert but our last boat before our Yamaha was a Tahoe and they advertised the trailer on it as galvashield if I remember right. Not sure how they did it but it was painted over galvanized and held up well. It was an 06 model and a friend of mine owns it and it still looks good. Never been in salt water but they said when purchased new it was salt water safe. Maybe at least give you something to research.

 

[Trannyguy]

Hey I just looked on their website and it’s still lists it as galvashield but I was wrong it looks like its powder coat not paint.

 

[Troy JK]

I haven’t tried it on galvanize, but I have painted over stainless steel by using etching primer first. It was on stainless windshield hinges on my sons Jeep (about 6”x6”). That was about a year ago and and still looks good.
I would ask around and maybe test on the underside before painting a whole trailer tho.

 

[J-RAD]

Has anyone ever heard of painting a galvanized trailer?

Of course there are ways to prep the zinc on the galvanized surface to make paint stick giving the best of both worlds - a clean higher end look while retaining greater rust protection, but being able to do something doesn't mean its a good idea. There doesn't seem to be much on the topic out there.

I remembered this thread. Where a member plasti-dipped his galvanized trailer. I guess he followed the example of another member as well.

https://jetboaters.net/threads/plasti-dipped-the-trailer.1504/

 

[Bizywk]

I remembered this thread. Where a member plasti-dipped his galvanized trailer. I guess he followed the example of another member as well.

https://jetboaters.net/threads/plasti-dipped-the-trailer.1504/

Tks @J-RAD. I missed that one. I've heard of plasti-dip successfully used for a wide variety of unique projects, but not on this scale. WOW. I hope it lasted for him. Plasti-dip isn't generally known for long lasting weather resistance so I wonder how often it needs touched up.

I'm still thinking that IF I do this, paint would be best as there are some very specific types/formulations that are recommended due to long term UV exposure and compatibility with paint resistant zinc in hot dipped galvanized metal configurations. Paint is used over galvanized all the time in construction for towers, metal roofs, supports, etc with a high degree of long term success in the weather. At the same time, I've never heard of anyone painting over galvanized trailers before - maybe because we don't see them up here. Cost on this project is low as I already have the equipment.

Just still wondering if it's a smart idea. If the galvanization integrity is maintained, the steel portion is well protected from red rust by the zinc. If the zinc/steel combination is painted, it would also protect against white rust/corrosion which happens to galvanized steel.

Besides trailer longevity/protection, I'm also looking at raw aesthetics. Galvanized trailers are rare here so the trailer looks don't compare well against a good looking paint job at resale time. I'm considering a really nice custom look that matches the boat/truck along with a few additional LED side safety lights and the electric over hydraulic brake upgrade.

What do you guys think? Has this been done before? Is this just too much overkill? The science appears sound but I like to learn from other peoples experience/mistakes whenever possible.

 

[Sonic Blue]

What about Line-X truck bed coating? Does anyone know if that can be applied over galvanized steel?

 

[zipper]

A few views on this. I did take a metalurgy class 39 years ago. If you don't use it...you lose it. I worked at IBM at the time. It was about crystal structures and facets while evaporating metals like Au, Ni, Sn etc. on substrates/wafers to create electrical circuits/devices on computer memory chips.

4 Steps to Paint Galvanized Steel | Monnig Industries

If you’ve ever attempted to paint over galvanized steel, you probably know that it doesn’t adhere the best.

monnigindustry.com

Colorgalv by Duncan Galvanizing

Get maintenance free steel corrosion protection with a beautiful architectural finish from Duncan Galvanizing's Colorgalv paint over galvanized steel systems.

www.duncangalvanizing.com

How to Paint Galvanised Metal - Rawlins Paints Blog

Galvanised steel enquiries to Rawlins Paints often fall into 1 of 3 metal paint categories; those wanting to paint already galvanised steel, repairing damaged galvanising, and those wanting to paint mild steel to be galvanised. For general painting of galvanised steel, clean and degrease with...

www.rawlinspaints.com

But I did stay at a Holiday Inn Express recently, lol.

 

[haknslash]

We paint over galvanized steel at work. What exactly are you wanting to know? Our paint process of dry powder. The only thing we do different compared to regular steel surface is we grind to get a smoother finish as hot dip galvanizing leaves a very rough surface. We use a hybrid polyester epoxy powder paint.

 

[AZMark]

They make specific primers for galvanized, just used it on some conduit here.
I would think if resale is your main concern then paint it at that time. Or just explain to the buyer why galvanized is better. Old paint is usually going to look worse than old galvanized. You’re kind of locking yourself into some future work to keep it looking good.

 

[haknslash]

Agree. Personally I’d leave it galvanized. Yea it won’t look as nice looking as a freshly painted brand new trailer but painted trailers don’t look great as the years and miles pile up.

 

[Bizywk]

We paint over galvanized steel at work. What exactly are you wanting to know? Our paint process of dry powder. The only thing we do different compared to regular steel surface is we grind to get a smoother finish as hot dip galvanizing leaves a very rough surface. We use a hybrid polyester epoxy powder paint.

I hadn't consider powdercoat. That's an idea. I don't have the ability to create that kind of heat to cure the paint for an entire trailer, so I'd have to take it somewhere, but powdercoat is more durable than normal paint. Definitely a good suggestion. Thanks.

@AZMark was on the right track. I wanted to know if it had been done so that whoever has done it, or knows of someone who did, might recommend either way based on their experience. I know how, just not sure it's a good idea. @AZMark 's argument against is that there would be increased maintenance over leaving it in its natural state.

 

[2kwik4u]

A few views on this. I did take a metalurgy class 39 years ago. If you don't use it...you lose it. I worked at IBM at the time. It was about crystal structures and facets while evaporating metals like Au, Ni, Sn etc. on substrates/wafers to create electrical circuits/devices on computer memory chips.

4 Steps to Paint Galvanized Steel | Monnig Industries

If you’ve ever attempted to paint over galvanized steel, you probably know that it doesn’t adhere the best.

monnigindustry.com

Colorgalv by Duncan Galvanizing

Get maintenance free steel corrosion protection with a beautiful architectural finish from Duncan Galvanizing's Colorgalv paint over galvanized steel systems.

www.duncangalvanizing.com

How to Paint Galvanised Metal - Rawlins Paints Blog

Galvanised steel enquiries to Rawlins Paints often fall into 1 of 3 metal paint categories; those wanting to paint already galvanised steel, repairing damaged galvanising, and those wanting to paint mild steel to be galvanised. For general painting of galvanised steel, clean and degrease with...

www.rawlinspaints.com

But I did stay at a Holiday Inn Express recently, lol.

You beat me to the Holiday Inn Express gag

Most new automobiles that have steel panels have a coating or treatment ahead of time to prevent rust should the paint chip. You can certainly paint over the galvanized surface, but you'll lose some of the inherent protection of the galvanic process along the way.

The general idea of galvanizing is that you build an oxide coating on the outside surface of the metal that is harder and more resilient than the base metal alone. Same premise as anodizing aluminum. You'll etch away some of that oxide layer with primer to get the paint to adhere.

The paint is probably an equal or better protecting agent than the galvanizing though.

Painted trailer fail from the inside out. Rarely does the paint fail and lead to rust intrusion, rather the internal passages that are dunked in salt water and not rinsed lead to rust and failure. The galvanized trailer has been dipped in a giant bath during the process, so it has internal protection already.

Theoretically, a fully painted trailer (inside and out) is best. I would wager an externally painted and internally galvanized would be a close second.

 

[Ronnie]

I’m not a metallurgist, just a hobbyist but I haven’t heard of anybody ELSE painting a galvanized trailer before. I however painted two roughly seven years ago. Here is how I did it:

In the garage or on the driveway, with the pwcs and boat still on the trailer, after wiping the trailers down with rubbing alcohol using spray on bed-liner paint from Home Depot for an estimated total cost of $70 (10 cans at $7 each).



I’ve never had or never noticed any long term problems with either trailer’s paint job and touch up is a breeze. That stated, if I were to do it again I would not use truck before liner, just flat or high gloss rustoleum (sp?). Why? Because truck bedliner paint has a rough surface which dirt settles into easily and can be difficult to clean off.

My pwc trailer has a dent in the storage box and the walls of the box flex so it’s not uncommon for the bed liner paint to crack and chip. This does not happen much at all on my boat trailer but it has happened on one of my fenders side walls (just a small spot about the size of golf ball). Again touch up is easy, just shake the can up and get to it. I have since sanded off all the truck bed liner paint from the folding part of the boat trailer’s tongue as the paint there was always chipping because I store the safety chains on top of it which I often also step on when getting into and out of the bow of the boat. The galvanized paint looks a little dull there but still looks good. I will post a pic of it later (if i

Clearly no over thinking here, just thinking at the time that I really disliked the look of my galvanized trailers.

Attached is a screenshot of before and after pics of my trailers. The link to my post is below, the trailer pics are about halfway down the page.

Yamaha Jet Boaters • View topic - My 2014 (2nd year) mods : warning, pic heavy

Jopedully this post is helpful and I don’t end up getting a lot of push back on it. To any who might say I couldn’t, shouldn’t, etc. I’d say I did easily and successfully (so far anyway) twice.