I think he just explained why this does not work well, ie once the air is
there the oxidisation starts, and any finish is not bound to the surface,
only the oxide. Normally one uses an etch primer and then a top coat if its
going to be painted, but on Brass if you want it to still look like brass
your options are limited. I guess you could make it passivated, ie plated,
but it seldom retains the brass look, tending toward a bit patchy rainbow
coloured brassy look. You could talk to a local plating company and see what
they say, but brass if you want it to look like brass has to be just
polished at least once a week. It eventually ends up green otherwise!
Brian

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The Sofa of Brian Gaff...

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On Wednesday, 11 July 2018 18:57:38 UTC+1, Nick Odell wrote:
On 11/07/18 18:13, rick wrote:
I have several door handles .. and interior side is OK ... but exterior
has dulled badly.
https://flic.kr/p/27WZ4dC

These are presumably brass (can't be 100% certain) at least look & feel
like.

It will take some effort to polish back up ..... are there any good
finishes that will protect them.
I remember doing this on a previous house - bought spray on clear cote
lacquer - didn't last 1 winter.
Speaking from the POV of guitar parts and brass instruments, the problem
is that oxidisation of the brass begins from the moment you've finished
cleaning so the finish is being attacked from behind as well as on top.
If you really want immaculate brassware I'm afraid you've got to polish
it regularly. Ask the caretaker at No.10

Nick

or lacquer it


NT