Powder coating as a marine finish

[mherrcat]

Any comments on the efficacy of powder coating as a finish in a marine environment?

I am working on reconditioning some portlights to replace the leaking ones in my 30+ and thought about powder coating as a possibility.

I was also thinking of patching some small areas of corrosion on the portlight frames with Interlux Watertite epoxy filler. Would that be compatible with powder coating? (Maybe a question for the powder coating company...)

 

[treilley]

I think it works ok when you have no corrosion but I had powder coated some parts that did and it bubbled very quickly. Now, I had no control over the process but the coater told me they specifically treated and pre-coated the parts to keep that fropm happening.

 

[Glyn Judson]

Powder coating stuff in a marine environment.

Mark, Years ago I had a Lofrans manual windlass powder coated (white) and it remained in good condition for many years as long as I had it. I've since cargo shifted it to David (Emerald on this list) where he fitted it to the foredeck on his E31. I hope he sees this note and will be inspired to chime in but I suspect the coating is still doing well. My interest in powder coating the windlass, aside from the vinyl on it bubbling off from the aluminum oxide under it, was my seeing a Bruce anchor coated in white powder coating years before. The owner had it done that way primarily in order to facilitate being able to see it on the bottom in our local SoCal (and relatively clear) waters. Pretty cool trick. Glyn Judson, E31 hull #55 Marina del Rey, CA

 

[mherrcat]

A little web research indicates that a chromate or phosphate chemical conversion coating applied to the aluminum prior to powder coating can help reduce "under film" corrosion.

I checked with one powder coating operation here in town and they don't do a conversion coat, but they can do an epoxy undercoat and a polyester or polyurethane top coat. (The polyester/polyurethane holds up better to UV.) Cost to do five portlights is between $110 and $160.

Since the frames I am using do have some small areas of corrosion under the mounting flange I am thinking the conversion coating route is the best way to go to try to eliminate as much future corrosion as possible.

 

[Emerald]

I've since cargo shifted it to David (Emerald on this list) where he fitted it to the foredeck on his E31. I hope he sees this note and will be inspired to chime in but I suspect the coating is still doing well. Glyn Judson, E31 hull #55 Marina del Rey, CA

Yes, it is doing quite well, both from a finish standpoint and as a windless