Motoryacht aluminum widow frames-gctid800871

[Guest]

Our 1995 4788 windows look... old, faded and need love. Has anyone painted or redone theirs?

[Guest]

I intended window frames! Thanks

[TenMile]

Yes. You have to scrape and sand them down very well. Have to get all the aluminum corrosion off -- particularly where it bubbles and pits. It's important to get on a good coat of Aluminum Primer -- there are several brands out there but I understand something with Zinc Chromate works best. You can then either brush or spray -- brushing can leave streaks but spraying can be tricky so I'd leave that one up to you.

[Uncle_Bob]

It's all in the prep. Any marks, scrapes, sanding ridges etc will telescope through the top coat and look awful. I used Zinc Chromate spray and topped with semi-gloss black Tremclad/Rustoleum. It evenly fades to a good match.

[MerlinV]

This old chestnut has been a regular topic ever since I joined BOC many years ago. Uncle Bob is correct about carefully preparing the surface and coating all bare aluminum with zinc chromate, otherwise you'll be doing the whole thing again sooner than you'd like to.

One additional observation, since repainting the frames on our 3258 back in 2002, the the surface of the corroded area (usually around the drainage slots) will likely need an aluminum filler, as the pitting is often too deep to sand it out smooth enough for a good finish.

I have a friend with a 2008 490 where the frames corroded and paint bubbled before the boat was two years old. The authorized factory warranty fix demanded that the drainage slots be ground out wide enough that no water would be trapped behind them. As the 490 window frames are powder coated white, the wider slots would typically be very noticeable, but the repairer removed the frames, re-anodized them after repair, then powder coated them again - an excellent fix, but why did Bayliner/Meridian let this become a legacy problem with most of their motor yachts for all the years before bonded in windows became the standard?

[green650]

"MerlinV" post=801217 wrote:
This old chestnut has been a regular topic ever since I joined BOC many years ago. Uncle Bob is correct about carefully preparing the surface and coating all bare aluminum with zinc chromate, otherwise you'll be doing the whole thing again sooner than you'd like to.

One additional observation, since repainting the frames on our 3258 back in 2002, the the surface of the corroded area (usually around the drainage slots) will likely need an aluminum filler, as the pitting is often too deep to sand it out smooth enough for a good finish.

I have a friend with a 2008 490 where the frames corroded and paint bubbled before the boat was two years old. The authorized factory warranty fix demanded that the drainage slots be ground out wide enough that no water would be trapped behind them. As the 490 window frames are powder coated white, the wider slots would typically be very noticeable, but the repairer removed the frames, re-anodized them after repair, then powder coated them again - an excellent fix, but why did Bayliner/Meridian let this become a legacy problem with most of their motor yachts for all the years before bonded in windows became the standard?

What is a bonded in window?

On the 32xx series, window frames can't be taken out. That's all that's holding the flybridge on. They fixed that design error with the 33xx.

[MerlinV]

What is a bonded in window?

If you look at any Meridian built after 2003, (490 is the exception) the windows are effectively frameless from the outside, and have no aluminum showing at all. Basically the windows are bonded (glued) to the structural frame. The downside is that most of them have very limited or no opening windows.