Lewmar window powder coating flaking off

[NPMR]

The black coating around our 13 year old Lewmar windows is flaking off.

I don't know why, of course.

Can someone recommend a suitable treatment? I feel this has to be an 'in-situ' repair, so maybe winter job. It looks daunting to remove the window and get it re-coated.

But what paint, covering, and how hard to clean up what currently looks to be secure coating?

 

[PCUK]

Whatever you do it won't last as aluminium is almost impossible to paint/lacquer/coat once exposed to the atmosphere. However, if you remove all the powder coating, lightly abrade, clean with appropriate thinners, apply an aluminium primer and then paint, it will probably give you a seasons use.

 

[Stemar]

The window frames on Jissel got cleaned up, and the corrosion pits filled with plastic metal, then several coats of Aluminium spray paint. They lasted a good while.

 

[rotrax]

We have seven large powder coated windows in our pilothouse. The powder coating is failing.

As an experiment I just did the bad bits of one, completely stripped the exterior of another and did that.

Neither have deteriorated since. The completely stripped and repainted one has limitations in its finish as it was brush painted in far from ideal conditions, but it is acceptable compared to the cost and drama of removing and re powdercoating.

I suggest you do the following :-

1. Using a good 'pull' scraper remove all the old finish.
2. Use a stainless steel brush in a dremel type tool and clean about a foot of the aluminium surround.
3. Use Hammerite 'All Metal Primer' and apply to the wire brushed area.
4. Do another foot or so with the wire brush, then primer, until all is done.
5. Finish with oil based black paint applied with a quality brush.

The reason for doing a small area at a time and working quickly is that Aluminium oxidises very fast. It will be oxidisation that has lifted the powder coat. You need to get the primer on very fast.

To PCUK-five years since I touched up the first window frame, still good. Four years since treating and repainting the complete frame, still good, definitly no further deteriation.

 

[PCUK]

We have seven large powder coated windows in our pilothouse. The powder coating is failing.

As an experiment I just did the bad bits of one, completely stripped the exterior of another and did that.

Neither have deteriorated since. The completely stripped and repainted one has limitations in its finish as it was brush painted in far from ideal conditions, but it is acceptable compared to the cost and drama of removing and re powdercoating.

I suggest you do the following :-

1. Using a good 'pull' scraper remove all the old finish.
2. Use a stainless steel brush in a dremel type tool and clean about a foot of the aluminium surround.
3. Use Hammerite 'All Metal Primer' and apply to the wire brushed area.
4. Do another foot or so with the wire brush, then primer, until all is done.
5. Finish with oil based black paint applied with a quality brush.

The reason for doing a small area at a time and working quickly is that Aluminium oxidises very fast. It will be oxidisation that has lifted the powder coat.

To PCUK-five years since I touched up the first window frame, still good. Four years sine treating and repainting the complete frame, still good, definitly no further deteriation.

That's good to hear. Long may they last!

 

[AntarcticPilot]

The reason for doing a small area at a time and working quickly is that Aluminium oxidises very fast. It will be oxidisation that has lifted the powder coat. You need to get the primer on very fast.

.

The oxidation isn't just fast - it's practically instantaneous. But I guess the special metals primer can handle a thin layer of oxide.