how-to "un" brush aluminum

I haven't had my hands on an aluminum PB, but I have done plenty of trying to make aluminum, stainless, etc look shiny. You can easily get sandpaper up to 1500 grit at an auto parts store. 2000 grit is available too, probably higher (though I've never seen it).

If you are starting with a brushed finish, you are going to need something a little more aggressive to start with. Maybe like a 320 or 400. Then you'd have to step up through the ranges of sandpaper that you can get. Maybe 320-600-1000-1500. At 1500 grit you are probably going to have a slightly matte, shiny aluminum surface. If you want "chrome" then you are going to have to use something finer still, like jeweler's rouge (available at Sears or a good hardware store) applied with a buffer (also available at Sears) That will leave you with a close to mirror finish. I haven't tried it, but seems like an car buffing compound would work well at that point for that last bit of sparkle. Aluminum takes a pretty good shine.

I don't think you can get there in one or two steps. For a really mirror finish, there's going to be some tinkering involved!

good luck!
mike

Goto a shop that sells car repair stuff. Pepboys etc. You want to go with a 400 and up to a 2000 grit, wet sanding is probably best. Then a rubbing compound, with a power buffer would make it easier. then a metal polish of some sort, and then probably a clear coat or something to keep it looking shiny. Don't know how well it will work on the thin metal casing, and I would probably try it with the case off the laptop so no dust etc gets inside. I started painting with case mods to my computers, and have moved on to repairing the finish on my car and refinishing wheels. It takes quite a bit of work to get it looking good. Actually, I think I'll try it on the aluminum piece off the extra battery I have. Also, the aluminum powerbooks are anodized, not brushed aluminum, so you're going to have to get through the anodized coating and into the untouched metal.

i'd agree too that working up to finer sandpaper and then switching to polish (Griot's Garage has a range of machine polishes to get a very fien finish). my only concern with such is a mod is how do you plan to keep the surface perfect once you get it to a mirror finish? that's something to consider.

It's not 'brushed', it's anodized. In order to polish it you have to remove the anodized layer. There are chemical strips that can do it, or you can use a mechanical process (like sandpaper.)

A little basic research will go a long way, google some keywords like {remove aluminum anodizing} and {polish aluminum}.

I briefly looked at the idea for my 12" AlBook and quickly decided it wasn't worth even looking at. Unless you get it re-anodized, you'll have a helluva time keeping the polished surface from oxidizing to a dull mess.

Now re-anodizing, there's the way to get a unique look. google {anodize aluminum color}. Strip, prep and re-anodize is a major PITA, but there's great potential for a real eyepopper of a 'Book

dan k

Not necessarily true. An automotive grade clear-coat will keep it looking nice & shiny.

that would be equally as painful. the powerbook would have to be completely ripped apart down to the bare aluminum pieces to get a good coat. and even then, the products you need to take care of clear coat aren't exactly friendly around computers. wax will get in some crevicies and will never come out.

just buy some chrome paint. i painted an ipod mini with some and it still looks as good as it did on the first day, and they are also anodized aluminium.

i know that the mini's were anodized, but i thought that the powerbooks were a brushed finish, not anodized

If you were to clear coat it, it shouldnt need too much maintence, as it isnt exposed to the elements. At least not as much as a car. The occasional wipe down should suffice to remove finger prints. If you were to go this route i'd advise only doing the lid. As well, if you later felt the need to wax it, use a dry wax, and mask off the vents, hinge area, etc... ...

[off topic: im posting this from a web browser im writing]

Anodizing is a chemical process. Brushing is a physical (mechanical, technically) finish.

You can have anodized aluminum that's brushed or smooth.
You can have non-anodized aluminum that's brushed or smooth as well.

IIRC brushing is done before anodizing. As anodizing makes the whole surface tougher (in addition to more oxidization-resistant), an anodized, brushed case would be very difficult to buff out to smooth.

As for its resistance to oxidization, I don't know if anodization protects only the outer layer of the aluminum, or if it goes all the way through. If it's the former, then Dan K is right and any "de-brushing" project on an anodized case that would turn out badly.

Matt

Anodizing, or anodising, is an electrolytic passivation process used to increase the thickness and density of the natural oxide layer on the surface of metal parts. Anodization changes the microscopic texture of the surface and can change the crystal structure of the metal near the surface. The process derives its name from the fact that the part to be treated forms the anode portion of an electrical circuit in this electrolytic process

i.e. it is a surface treatment.

IIRC, someone did remove the anodized surface f a 'book lid, and polished the underlying layer to a mirror finish which was then clear-coated. Hell if i can remember where i saw that tho.