Aluminimum protection

Can anyone recommend a clear laquer for protecting an aluminium surface from fingerprints and long-term corrosion? I'm making actuator buttons for the front panel switches from aluminium rod; after lengthy experimentation I am confident I can get a reliably decent finish, but I'm worried about the longevity of the surface. I'm intending to have the front panels themselves professionally anodised black, but I want to leave the knobs in their natural colour (and I don't want the bother and expense of having them individually anodised anyway).

Alex
 
well, you can have things clear anodised so that they retain there original colour ..... as far as laquer goes, not many things reliably stick to aluminium long term .... personally i'd go for clear anodising, it's less trouble and will outlast pretty much anything else .... sure it costs a bit but so will recoating the knobs every 6 months.
 
Alex,

mechanical designer speaking here, have to second AudioFreak's preference.
Nothing beats anodizing properly done by a pro. It is wear-proof, chemically inert, long-term stable. And it bonds to the surface better than any lacquer, it forms a coating penetrating the alu's surface about 13µm deep and adds further 6-7µm to the surface. Anodized parts do not only retain thei original colour but also their original surface quality. They stay exactly as rough as before.


One xception: if you want to protect the surface from tiny sharp shreds and stones, better take a powder coating remaining a bit elastic. but ipresum this is not the case in your application :)
 
if you must 'lacquer'

Old fashioned shellac is an amazing substance. It is extremely adhesive and sticks to and seals over pretty much ANYTHING that is ever encountered in the woodworking world. I bet it would glue itself right on to aluminum too, as long as it's not mirror polished. The other property it has is compatibilty with almost all other finishes. So you could shellac your buttons, then overcoat with some hell-for-stout high tech urethane or something (shellac itself is quite durable too, but not super mechanically so).

For all the trouble this would be, though, I'd probably go w/ the clear ano.

Luck
Sanaka
 
Aluminum

If you are going to use shellac, or any varnish/laquer/acrylic coating, make sure to wipe down the surface with an alcohol -- methanol (wood alcohol) to degrease the surface -- shellac is beautiful, best when you purchase the flakes and mix with meOH yourself.

i've had good results with Deft which is a laquer like surface -- dries quickly and pretty hard, builds layers quickly, but very flammable so best used outdoors.