Bronze cleaning

[Pelorus]

Hi All. I have a very old bronze anchor windlass. What would be the best way to restore it to its former glory. Thanks in advance.

[wingless]

Welcome to the forum.

My assumption is that the windlass was polished, not rough casting. If it was polished then any metal polish will restore it to looking like polished brass.

If it is rough cast, then this reply shows how I polished bronze to looking like polished brass.

Note, do not abrasively polish surfaces that have a functional purpose, because the polishing will dimensionally change the part.

[tkeithlu]

Pelorus, pictures might help. Also, what is your goal? Bright "brass" as in Winglesses project and procedure, clear coat so you don't have to do it over each weekend?

There are three ways to tackle it, first being mechanically with a wire brush on a grinder head. The second is mechainically with an abrasive cleaner. The third is chemically, basically with ammonia, which dissolves copper and tin oxides.

Be aware that a wire brush leaves a very smooth surface, to which a clear coat or paint may not adhere too well.

I clean our large bell with a wire brush and then spray on a clear coat. That lasts many months but not years in its exposed position on our foredeck. The patina is dark, probably because the wire brush does not remove everything. A chemical finish would be bright (Wingless), but would show every tiny bit of tarnish or miss in the clear coat.

The good news is that you can proceed until you see what you want. Short of large amounts of heat, you are not going to harm the bronze.

[Manateeman]

Hi. There is nothing in your profile about you or your boat so I’ve got to guess it’s the primary way you use to retrieve your anchor. And it’s an old windlass...
Correct? It might be time to strip it down, clean all the guts and put it back together with nice new grease. It’s sometimes easier to polish. If you take care of the insides of the windlass, it will reward you with flawless operation.
Resist the urge for perfection. Even manatees have algae on their backs.
Happy trails to you.
Mark, no spit and polished manatee

[tkeithlu]

And, when you get it all together, you can tie a rope to it and use it as a really classy manatee bopper.

[Mike OReilly]

My boat has a original manual bronze windlass, along with bronze ports, cleats, belaying pins, and probably a bunch more stuff. It all has the lovely green patina colour that marks time on the salty seas.



Why would you want to change that?


If you want to keep your bronze nice and shiny it will be a constant and ongoing effort if you're on the oceans.

[wingless]

Originally Posted by wingless

Welcome to the forum.

My assumption is that the windlass was polished, not rough casting. If it was polished then any metal polish will restore it to looking like polished brass.

If it is rough cast, then this reply shows how I polished bronze to looking like polished brass.

Note, do not abrasively polish surfaces that have a functional purpose, because the polishing will dimensionally change the part.

This image shows polishing the rough cast bronze exterior surface while leaving the functional surfaces untouched and intact.

These parts look great after well over a decade w/o additional effort.

[Manateeman]

Hi. I agree with Capt OReilly that the patina of old bronze is nice. I built a boat with a lot of high quality exterior bronze on a black hull with a white bulwark.
It took a while, but all the bronze turned a beautiful light green called verdigris.
It’s copper carbonate. I had a wealthy woman ask me how to turn her yachts polished bronze into verdigris...just the opposit of what you want to do. Jewelers used acetic acid and I think cupric nitrate to try to get verdigris green. What you want to remove others cherish. It’s what makes yachts so interesting.
A very long time ago when artists made their own paint and worked on wood not canvas, copper carbonate might have been a material. I’ll look this up. It’s slightly poisonous and bronze dust will give you green hands. It’s a fantastic boatbuilding metal.
Happy trails to you.
Mark, bronze loving manatee