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  for Metal Finishing since 1989
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Alum. Polishing "How to get nice finish"

I work in a jobshop and we have a polishing question for alum. assemblies,it is for an alum. box the material is only 1/8" thick. We need information on the best way to polish the material. We have tried disk pads, they leave swirl marks on the material. Can someone please give me an answer as to how we can get a nice finish without swirl marks or scratches? Thank you I will look for your reply. Lois

LOIS YANNAYON
- ORRVILLE, OHIO USA
2000

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2000

Lois:

You have started out with an appropriate method to begin the finishing process. I assume you're using some type of orbital sander with an abrasive pad. You're absolutely correct that you will leave "swirls" on the surface.

You haven't finished the process though. My experience with aluminum is that you start out with the finest grit possible to remove any scratches or pits that are apparent in the aluminum. Sometimes this can be as coarse as a 120 grit or as fine as perhaps a 320 or 400. You should finish finish the aluminum with progressively finer grits 120,180,220,320 for example and then buff the surface.

Depending on the finish desired you can buff with a bias cotton buff with brown tripoli buffing compound ⇦this on eBay or Amazon [affil links] . If you desire a higher lustre, buff again with a cloth buff with coloring compound (no abrasive).

Your polishing and buffing distributors can be of great service in giving you advice. I'd contact them as well to see what they recommend.

Daryl Spindler, CEF
decorative nickel-chrome plating - Greenbrier, Tennessee

Lois, Try a orbital sander or D.A. sander with 400 grit or finer. I polish a lot of truck tanks, etc., and find this will work well getting the finer scratches out. After that I use a 6" cotton cutting pad w/ j jeweler's rouge ⇦this on eBay or Amazon [affil links] then I use a softer pad w/ jeweler's rouge and still a softer pad w/ you know what. This procedure seems to work well with me. Also a lot of practice helps.

Scott Byler
truck detailing - Gordonville,Pa U.S.
2000

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I have two relatively small bags of uncut emeralds. I live in Ft. Lauderdale. My 15 son thinks we purchase the machine to cut them that he could cut them? Where can I go to have it done professionally? Again, I live in Ft. Lauderdale, FL.

Thank you,

Barbara K. Wirks
- Ft Lauderdale, Florida, USA
2002