Polishing Aluminum

[boguing]

Simple question, and one which I wish I'd thought of asking you lot over a week ago.

I'm refurbing my Dad's old Anglepoise lamp - a lamp which lit the desk where he Chief Engineered the RB211 - so it is aviation connected!

Autosol Metal polish did a great job on the tubes, and a fantastic job on the steel base, but nothing I've tried will get a mirror finish on the shade. It was flatted back to 1200 grade, best so far has been AutoGlym, but although it's very very smooth, it just won't shine.

I suspect that there may be Ammonia present, although I can't smell any.

What would you use, and where would I get a tiny bit?

John

[Loose rivets]

If you really want to invest some time, try jeweler's rouge. It has to be polished with a mop that is going at some hundreds of feet per minute.

I have got a shine on quite hard steel that just doesn't seem to rust for years, and brass looks like gold. Never tried aluminium though, so be careful.

[roljoe]

Hi,

I remember using one of the best compound ever manufactered while working on bike parts in aluminium.

It was proposed by "Du pont de Nemours"..not sure this product still exist..Good hunt..

[RVF750]

Are you sure the part isn't plated in some way? Might sound daft, but if it is, then that might be your problem.

[Mark 1]

Most of the polished aircraft that you see usea polish called Nuvite, which comes in several grades to progressively build up the level of polish. Involves many, many hours work on an airframe; maybe not so much of an issue for you.Progressively refining the polish grade after removing all traces of the previous grade is usually the way to go.

Google lapidary suppliers for graded carborundum pastes and cerium oxide polish.

I think sulphur is more of a problem in polishing lower grade alloys.

[johngreen]

Try using common or garden Brasso but bear in mind that the cloth you use needs to be very soft and spotlessly clean or it will scratch the surface as you polish it.
As you work it will make a horrible black mess but once this is rubbed away, you will find the shine underneath. I have often used this to get a mirror finish on alluminium parts.
Maybe test on a less conspicuous part first though....just in case!

[forget]

If all else fails - have it chrome plated.:ok:

PS. That assuming you can chrome plate ally. :confused:

[billynospares]

Wadpol aircraft polish

[Von Klinkerhoffen]

Agree , Wadpol is pretty good , Nuvite is even better !! Which Chief Eng.... Sir Stanley Hooker ??

[boguing]

Hmm, plenty of food for thought - thanks all.

Loose Rivets, have found a supply of rouge - did you use a leather pad? The hundreds of feet a minute isn't much of a problem. I made a mandrel up so that the shade is in the jaws of my Bosch drill! No sweat.

I did the 180 grit through to 1200 grit wet on the pressed steel base cover. The Autosol metal polish brought that up to a mirror finish - I had no idea that raw steel could look that good. And funnily enough, I wondered how it would stand a damp environment, so left a few drips of tapwater on it overnight, in a warm kitchen. Next morning, nothing but limescale. Do you think that the burnishing effect traps the Carbon and just doesn't let the water get a hold? Weird.

billynospares / Mark 1 / Herr Von Klinkerhoffen please fight it out between yourselves. If the rouge doesn't work I'm going with Nuvite, as it stands. Two to one.

johngreen - funny enough, I left my last bottle of Brasso at the ex's. Would certainly have tried it. Peek worked quite well in tiny areas, got the shine, but as you say, the black mess... but once cleaned off, no shine - which is why I reckon something else is in it which the metal doesn't like.

Dash & Thump. No - if it was plated - it ain't now! It had been painted externally, but raw internally. I'm thinking that it's 'Birmabright' which Land Rover used extensively post-war. Slightly corrosion resistant without anodising. Although the drawn Alu tubes making up the 'mechanism' responded beautifully to the Autosol, just the shade that doesn't.

forget. Too much money! Although, yes it is doable. But if you saw the finish I've achieved on the steel, you wouldn't even go there!

roljoe. Will try the others, and if that doesn't work, Google will be a new best friend, again.

Herr Von Klinkerhoffen. Harry Cook, left 1971 - for obvious reasons.

ps. Once I have a mirror finish - is there a best polish to slow oxidation? Was just going to use AutoGlym resin stuff, but since I have digits on keyboard...

Promise to put pics up when it's done.

[Tree]

Nevrdull

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