Protective coating for polished bronze

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Tallystick
Skilled Systems Installer
Posts: 177
Joined: Fri Sep 09, 2011 10:54 am
Boat Name: Nostalgia
Boat Type: Pearson Triton Yawl

Protective coating for polished bronze

Post by Tallystick »

What products have been found to be effective for protective coatings on polished bronze parts? The window frames and portholes for my boat are polished to 600 so far. I'd like to apply a protective clear coat to keep them shiny after the last few polishing steps. Online I saw a few specialty coatings for outdoor use on polished bronze statues that seemed promising. There are also spraycans of outdoor clear lacquers for metals at HD & Lowes. Can someone who has experience on this provide guidance?
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Rachel
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Re: Protective coating for polished bronze

Post by Rachel »

I don't have experience with it (I like the patina bronze develops), but I remember that Tim Lackey used clear lacquer to coat the polished bronze port frames on his Triton. I think he had to re-do them fairly often ... maybe annually? That would be for a northern boat stored under cover for about half the year.

Unless my memory is off, I think he would probably not choose to do it again, but since he had, he kept maintaining them.

Speaking of the past, I remembered that there have been several discussions about this, so I did a quick search (bronze and lacquer were my search terms) and came up with these threads that may make interesting reading:

Tim, how is your lacquer-over-bronze holding up?

Deadlight frames refinishing

Restoring bronze/aluminum hardware

How does everyone keep polished brass from tarnishing?
Tallystick
Skilled Systems Installer
Posts: 177
Joined: Fri Sep 09, 2011 10:54 am
Boat Name: Nostalgia
Boat Type: Pearson Triton Yawl

Re: Protective coating for polished bronze

Post by Tallystick »

I like the patina as well, and I'll likely let my bronze go green eventually, but I'd like to keep it shiny for awhile since she'll be newly rebuilt. The last thing I want to do is put on a lousy clear coat that fails quickly and then has to be removed. Maybe the best option is make the parts highly polished, and keep them up with brasso until I get tired of the shiny look.

If I do go with a coating it sounds like it needs to be somewhat flexible to accommodate thermal expansion of the bronze. Possibly a light silicone gel like is used on auto windshields would be sufficiently waterproofing to increase polishing intervals. That stuff is at least easy to remove if it doesn't work.
Tallystick
Skilled Systems Installer
Posts: 177
Joined: Fri Sep 09, 2011 10:54 am
Boat Name: Nostalgia
Boat Type: Pearson Triton Yawl

Re: Protective coating for polished bronze

Post by Tallystick »

Thanks for the suggestion Glenn. That looks like a good product to try. I also like the tumbler idea. I've been using brass wire wheels and on some parts first treating with HCl. It's always nice to automate things, especially tedious polishing.
Hirilondë
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Re: Protective coating for polished bronze

Post by Hirilondë »

The problem with using any product in an attempt to keep metals looking polished is that they will fail. And now you have a mess. Not only does the item need polishing again, but you have to remove all the old coating. This is the primary reason I like bronze so much. I let it patina and quit fussing right there.
Dave Finnegan
builder of Spindrift 9N #521 'Wingë'
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