Powder Coated Masts?

[mattp]

Anybody have experience with this?  We have a local fab shop that has an operation that can handle the finished length (minus end caps, wooden plugs, and epoxy that would probably melt) and I know it would be a very durable finish.  My concern is about the extra weight in the worst place; up high. 

[Phil Garland]

Not enough weight to worry about vs. the benefit of protecting the aluminum

[Howard]

Matt:

 

Can't help you with the powder coating.

 

A friend of a friend has become a pretty decent shade tree type guy with automotive paints......normally paints used cars, trucks and farm equipment. He did a decent job on my Spindrift mast sections with an epoxy primer, paint and clear coat. I recall the major concern was getting the amount of flex additive right. They look good so far and the two part automotive paints are durable. That is my current plan for finishing the Princess masts when  the time comes.

 

Of course all that is on the outside of the masts. Not sure what becomes of the inside, unless one simply lets them oxidize and rely on that to protect them.

[mattp]

Not enough weight to worry about vs. the benefit of protecting the aluminum

Philip: Did you powder coat the masts on your CS17?I also have a little concern about the coating affecting or being affected by the flex of the masts.

[Phil Garland]

Matt,  we used a special Sherwin-Williams urethane coating system called Genesis...it is designed for automotive and OEM production painting...it is a new product that we were trying out...its advantage is you can prime and paint topcoat in one process rather than wait and sand between coatings.  So far it has worked out fine on our test boats and is now being used on one of our OEM boats, the new J-88.  I think any good quality urethane with a primer for aluminum would be fine for your masts. 

[Hirilonde]

 I think any good quality urethane with a primer for aluminum would be fine for your masts. 

I think the primer for aluminum part is the key.  For the boom of my Renegade I used Awlgrip's zinc chromate epoxy primer made just for that purpose.  It worked superbly.  I used Alwgrip's 545 as the primer on my Spindrift mast and had issues a couple years down the line.

[Charlie Jones]

I've used Zinc Chromate primer on 5 different masts- works quite well.

 

I did a 21 footer's mast about 10 years ago- and over coated with 2 part poly paint- still looks great except where it's been scraped

 

You can buy (at least here you can) Zinc Chromate in spray cans at our Ace Hardware

[Scott Dunsworth]

My only concern would be the high heat it takes to powder coat removing or weakening the temper of the alloy.

[PAR]

The heat of powder coating (350 - 400f depending o product) will have no affect on the aluminum's temper. Powder coating is a good option if you can afford the added thickness.

[Ken_Potts]

Is there really any problem with not coating aluminium at all?  I thought bare aluminium just became anodized with exposure to the environment.

[PAR]

Aluminum oxidizes with exposure, which in itself is protective, though not attractive. Anodizing is actually plating (like chrome on steel). Unlike steel where oxidation actually destroys the base materiel, aluminum just develops this chalky "patina"  and isn't structurally compromised. Many thousands of production boat masts have survived many decades, without a drop of paint or other coating.

[Ken_Potts]

I'm pretty sure anodizing is oxidation, not plating.  I'll check on it and report back...

[PAR]

Technically, we're both correct, though anodizing is an electrochemical process performed on nonferrous metals (titanium, magnesium, etc.). It's an anodic oxide electrically "activated" (aluminum is the cathode while in the chemical "tub") with the substrate, rather than being applied, like paint or plating. I guess you could call it a highly controlled form of forced oxidation.