Hi y'all,

Maybe someone somewhere can help shed me some insight how to polish aluminum to a chrome like finish.

You'll need to first start off with sandpaper to work out all of the deep scratches in metal. I usually start with 220 unless there's some serious scratches. Once all of the scratches are gone, switch to progressively finer sandpaper (320, 400, 600, 800....) By the way, I usually wet-sand, and use a little bit of dish detergent in the water to keep the sandpaper from clogging.

You'll find that as you get to finer and finer grades of sandpaper, you'll be approaching a mirror finish. However, to get the most brilliant shine, use a buffing wheel or a vibratory tumbler with corncob media. Either way you can get a mirror finish on aluminum, which will look like chrome.

Check out www.caswellplating.com They've got a good HOWTO on buffing aluminum (http://www.caswellplating.com/buffs/buffman.htm?PHPSESSID=a37b2e70e1311aa920d376a6b436d52f), and they also sell buffing supplies.

Here's a pic of a piece of polished aluminum. You can get a much flatter surface than this (notice the machining swirls), which will yield a better reflection.

http://www.logiccooling.com/images/nem_clear2.jpg

a few tips:

1) use WD 40 or Tap Magic for lube, not water. Water will turn the parts black and ugly

2) after using paper, go to red scotch brite, then grey finne scotchbrite...use same oil her too

3) when you use a buffing wheel, use green wax first, then white wax to finish up....

4) for extra bright shine, some hand polishing with Flitz can help too..;)

...Mother's brand polishing compound (usually found in automotive stores for dressing up billet wheels). Once you have a finish you can buff in a mirror with this stuff in seconds...

Here's a couple more pics. They're both lapped up to 1000 grit sandpaper. I wouldn't call this a mirror finish, but it's a good start. (Yes, they're both copper, but copper and aluminum will polish up very similarly).

http://www.logiccooling.com/images/lap1.jpg

http://www.logiccooling.com/images/lap3.jpg

Second vote for Mother's mag and aluminum polish here! Cheap and very effective.
Ive also used it lap the dovetails of my various machines and works great too.
Ive seen that several people on the internet have used it for lapping dovetails and such with great results as well.

You can also consider using diamond paste for the final polish. a 4 micron paste should do the trick.....
It works fine on moulds, i never tried to polish aluminium with diamond paste.

Klox

Never used "Mother's mag and aluminum polish " but Flitz has a warning on it to use welding goggles to view after polishing.:D

Is the Mother's mag and aluminum polish abrasive at all?

Ken

I have use the Mother's polishing compound on several projects and have always been amazed at how little effort it takes to get a sheen. It feels like light grease and its glossy smooth texture makes it look like there isn't any abrasive in it. (The abrasive pastes I've used in the past were dull and thick). I have always wondered if it somehow micro-etches the surface...

'course, maybe it embeds photons or micro LEDs... laser technology!

Holy Cow!!! I just tried out Mother's for the first time, and I'm amazed at the extreme sheen you get with such little work. It's really some amazing stuff. Thanks for the tips, guys!

Nothing like a convert! Been using Mothers on all our Stainless Steel on the boat since 1990 - it is awesome.
If you need to clean stainless (may not be a choice for aluminium) MDR metal polish/cleaner - most chandelerys can get it, but you pay a yachties price for it!
:cheers: Jim
Note if you want a protected finish but satin, not high gloss, use the 3M green pads for application -- but then for your ap you wanted shiney stuff!

Ok, it's time for me to show off. Enjoy!
http://web.umr.edu/~bpryor/oc/lap4.jpg

NeoMoses,

Cool piccy, shiney too! What were the steps that got it's shine?

I'm looking for both FLAT and SMOOTH finishes, so I do all of my lapping on a granite surface plate that's flat to 0.0001".
I start out with 220 sandpaper to work out all of the deep scratches. When the surface is consistent and all the deep scratches are gone, I work up to progressively finer sandpaper until I've gotten to 1000. (220, 400, 600, 1000 is my usual progression.) I use a mixture of warm water and dish detergent to keep the sandpaper from clogging. (WD40 may be a better method, but I've never tried it.)

And recently, I've started finishing with Mother's Mag & Aluminum Polish, which gives the amazingly shiny finish you see there. It's quite easy if you follow the directions on the bottle.

ok this may sound like an odd question but i have a reason...
Is mothers mag and aluminum polish ok for polisihng mag?
the reason i ask is becasue lots of stuff has become known as 'mag' in automotive circles that is really just steel, especially in wheels...its become a design word more so than a construction material.

You bet, as is Flitz. Everyone has his or her favorite, mine is Flitz which is great for Gold, silver, factory gun bluing, SS, Fiberglass, plexaglass and more as well.

Ken

I use Mothers on steel and aluminum. It normally take 5 minutes for a mirror like finish on my aluminum parts:D

Quick note- If you are doing a lot of parts and want a permanent shine, consider Nickel plating, or even Chrome.

I've had some aluminum supports plated, and they come out really nice.

Zeph

not really the metal worker (yet) but do use mothers stuff on all my cars ..... great stuff!!!!

Neo; please can you use the term Wet/dry emery paper; sandpaper sounds like we are trying to polish up wood :D

I'll take note. It must be a regional thing, I call all grades of abrasive paper (36-2000) 'sandpaper.' However, if 'emery paper' is a more widely used term, I'll start integrating it into my vocabulary. I hate to sound uneducated. :) So, is sandpaper the rough, dry only paper used for wood sanding and wet/dry emery paper the stuff commonly used for metal finishing and wet-sanding?

I agree with the procedures and the products but.. what about protecting the mirror finish? what you recommend? I've done some OverClocking and there is no need to protect the mirror finish because we look for a flat and smoot surface that will be in contact with the CPU, and other areas don't care, but when we need mirror finish for a wiewable product what is the correct procedure to make it last longer?

/u

I did send all my alu parts for anodizing before. Absolutely outstanding finish and a surface rock solid and scratch safe, and besides that the surface can be coloured. I really recommend it.


I found this one for you DIY:ers: http://www.focuser.com/atm/anodize/anodize.html
More information: http://www.anodizing.org

For myself, I have very nice connections to an anodizing company so I don't have to deal with the liquids. :)

Regards,
Sven

Yes, anodizing is probably the best way to protect aluminum while leaving the polished aluminum look. You also may want to look at powder coating, although it's going to hide the nice polished surface you just made.