Putting a Matt Finish on Brass

[Ships_Cat]

I have some small brass fittings which are shiny brass but want to put a matt finish on them. Apart from attacking with fine emery/sandpaper has anyone had any success with some other method?

The items will be inside a dry boat so future weathering is not an issue.

Thanks for any feedback.

John

 

[youngwrinkley]

You could try getting them sand blasted?

 

[LittleShip]

Put them outside for a week or two..............that'll do it! /forums/images/graemlins/laugh.gif

Sand blasting will give you the effect if left a while, at first it maybe like an eggshell finish.

 

[tcm]

yep, beadblasting. This is the thing for olde brass engine parts to look real rather than overly "bulled up", sort of frosty yet new and with no cack left in the crevices.

 

[richardandtracy]

I can add a fairly long lasting 'temporary' solution.

If you varnish the brass with a clear matt interior varnish, you'll get a matt sort of finish. The dulling of the gold colour you normally get as the brass corrodes will be delayed too. I say this is a 'temporary' solution because the varnish always scrapes off over time.

Regards

Richard.

 

[pappaecho]

Cillit Bang contains an acid which instantly turns shiny brass dull. Probably toilet descaler, which contains phosphoric acid will do the same. Dont expose the brass for very long - just enough to dull the metal

 

[Ships_Cat]

We don't get Cillit Bang here in NZ as far as I know, but I have some stuff with phosphoric acid in it. Seems the easiest, so will experiment with that first.

Thanks all for the ideas

John

 

[BrendanS]

Just as an aside. Why do you want to matt finish the brass?

 

[Gunfleet]

Is it the case that you want an 'antique' look? I happen to know that suspending them over a small container of ammonia with a cover over it will do that trick. The longer they stay there the more antique they get - an antique dealer friend told me it's a way they use to match brass fittings.

 

[Ships_Cat]

Hi Brendan

They are small ring pulls going into some small light sole hatches so was looking to kill the shininess/reflectiveness of them against the matt finish of the flooring. They are going in a galley where the floor covering is a grey radial rubber so also wanted to kill the shininess and age them up a bit so a little more friendly against the grey.

Was originally going to use ss but nicely made ones are very expensive and can look a bit deckie hardwarish on the sole although would fit in with the grey. There is ss hardware in the galley bench tops for the frig and freezer lids and that fits in ok with the white bench tops tho.

The timber in the boat is a mid to light yellowy brown (NZ Tawa) and there is trim of that in close proximity to where the pulls will go. So was going to kill the gloss on the brass and age one up a bit and try it unfitted to see if that looked ok as the colour match sounds a little risky on first blush - if looks ok then do enuff for all (only 3).

A very grey metal or finish like anodised aluminium would be ideal but haven't ever come across similar hardware in that. Have thought about plating the brass with something that gave a similar finish but nothing comes to mind.

John

 

[BrendanS]

OK, quite small items then.

If you can get hold of it, then hydrochloric acid will do the job quite nicely. Depends on molarity of solution, just dump in and take out and rinse in water once desired effect achieved.

The other way of doing it is what they use to age silver, and may be worth trying with Brass - boil an egg, break the white up, and place rings and egg white in a small sealed plastic bag for 24 - 48 hours. The sulphides in the egg white cause a patina. On silver, it makes the surface black in 24 hours, then can buff to level of grey required. Similar process should work on Brass I suspect

 

[Ships_Cat]

Thanks Brendan.

Yes think can still easily buy HCl as Spirits of Salts in hardware shop/plumber's supplies as used for cleaning before soldering.

The boiled egg white sounds interesting and know the black colour they give silver. Will impress too as after secretly using them I can mash the yolk and used white up with a bit of curry so's can use it in sandwiches - all'll think "What a nice Dad, sometimes. Wonder what has come over him".

John

 

[BrendanS]

Watch out for the stained whites, which will discolour if in contact with the metal! They might not be so impressed if they have black egg yolk in their sarnies
(haven't tried it with brass, so not sure which colour the whites will go)

 

[Ships_Cat]

How It Turned Out

Fetched the brass ring pulls which were lightly lacquered and quite gold coloured. Tested them against a grey swatch and did not look as bad match wise as I imagined.

Used 600 wet and dry to get the lacquer off and found that light circular sanding with the worn part of the paper gave a light matt finish. Was going to try HCl if that hadn't worked - several suppliers of that close to us, but not needed.

Looked into the ammonia suggestion some more and decided to use that first as had it on hand (actually an ammonia based cleaner with wetting agent in it), boiling an egg was to be next try. The cleaner wetted over the surface (which I don't think anhydrous ammonia would do) and after an hour or so had given a distinct light grey cast to the brass with some bluishness where longer/more exposed.

I then used some ammonia based lightly abrasive silver polish to lightly hand buff them and turned out about how I hoped. Brass but doesn't look too yellow or gold and with a grey cast. How long the finish lasts I don't know but probably long enuff for natural ageing to take over - it seems quite hard. Not the sort of thing one would do to ones fine brass lamps, barometer and clock but to go into the sole and kill the sparkly shine and yellowness for colour matching it worked.

Did the screw heads too but kept ammonia off the screws themselves - one reference said ammonia encourages stress corrosion in brass and while probably not an issue, breaking brass screws always is, so played it ultra safe.

So thanks to all for the various ideas, whether used or just kept in mind as alternatives or for next time.

John