Tarnish on sides of clock and barometer

[Halo]

Just planing jobs for when I can get at the boat !
I have a pair of these instruments screwed onto a saloon bulkhead. They are brass coloured metal and the sides of both have tarnished and feel rough like rust. I suspect they started out very shiny with a laquered outer layer. I would like to return these to a nice finish but suspect they wont polish up and retain a finish. Has anyone had the same problem and sorted it ??

 

[andsarkit]

I have used Rustins Metal Lacquer on some bronze deck fittings and was pleased that it has lasted 2 years so far. It should last even longer in the cabin.
Thinners might soften the old lacquer and then just hope it polishes up well. It will probably depend on the original quality of the brass.

 

[James_Calvert]

They are almost certainly brass which should polish up very nicely. Getting the old lacquer off will be the challenge.

Once you've got it off you may wonder about re-lacquering. Polishing brass can be very satisfying if you have the time and inclination.

 

[ithet]

They should polish up very well. If you can completely remove the brass case then putting it on a boiling solution of caustic soda should remove the old lacquer quickly, otherwise fine ss wool. Polish with brasso or similar then thoughly clean then dry and as above use rustins metal lacquer or similar. Then wait for the tarnish to slowly reappear?

 

[neil_s]

Don't bother with the lacquer, just keep a tin of Brasso on board. Only takes a minute.

 

[Tradewinds]

Tomato sauce on plain brass is surprisingly efficient at cutting through the green crud. Finished off with fine polishing pads then Brasso.

Very satisfying.

Yes, I know one's a barometer and the other is a clock - these are the only photos I took of the process .

 

[PeterWright]

Hi,

Most clocks and barometers are lacquered when new and Brasso takes forever to cut through the lacquer so strip that off first. I don't like boiling caustic so I use Nitro Mors or similar paint stripper which gets it off if you leave it to soak for 20 minutes. If the brass is at all pitted, it takes forever to polish the pits out with Brasso, they come out much quicker with a bit of very fine wet 'n'dry. The scratches you leave will then polish out easily with Brasso. Once they're gleaming, it's up to you whether you lacquer again, Plenty of suitable lacquers available on the internet - aerosol is much easier to apply uniformly than a brush.

Peter.

 

[vyv_cox]

Problems arise with cheaper instruments that are made from steel with a brass coating. If the brass has pitted right through to the steel it may not be possible to recover.

However, I have a clock that is made from brass sheet, rather than cast. It was very dull and pitted when I bought the boat, so much that I did not touch it for years in case it would not survive polishing. Eventually I bit the bullet and it is now gleaming after hours of Brasso attention.

In the very worst cases it might be worth abrading with fine wet and dry, maybe 600 or 1000, before repolishing.