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How to polish my aluminium, please?
I sandblasted my aluminum swing arm on my motorcycle to remove the painted surface. now I am trying to get it to shine like chrome. I am trying to use fine sandpaper with no luck. How do I get what I want? Or do I?Reece Kalfell
- Billings, Montana
Reece, Depending on how deep the sandblasting is You may be able to sand them out...I wouldn't try doing it with a fine paper though...I would probably start with at least a 180...I have done that too in my excursions with aluminum...and I have learned...NEVER SANDBLAST ALUMINUM =)
If you have a hard enough wheel and some tripoli [link to product info at Amazon by ed.] compound and a little experience you can do it. If not consult a professional.
happy polishingBarbey Richardson
plating shop - Lyman, South Carolina
My company buffs fuel tanks, bumpers and hood crown assemblies for Peterbilt Truck Company. Your project is more complicated than you perhaps first realized. Ms. Richardson is absolutely correct in that sandblasting is terribly detrimental to the aluminum surface. What you'll have to do is use the finest grit polishing grit sandpaper that will remove the sand blast surface.
You'll need to go progressively finer and you'll probably need to finish out with a 400 grit finish that could be buffed to a mirror finish. This will require the use of cotton buffing wheels with tripoli compound and you could get the proper shine with a cotton buffing wheel with a dry chrome rouge.
I doubt that you'll be able to polish the sandblast surface adequately to give yourself the mirror finish you're looking for though. My advice is to take the swing arm to a professional metal finishing shop where they have the equipment and expertise to adequately polish and buff your part.Daryl Spindler
- Portland, Tennessee
I appreciate the comment you made about me, and agreeing with me. I have only been doing this type of work since June and it's nice to have someone comment. This job is unlike any other I have had and I love it. The neatest thing is when a man comes into the shop and finds that a woman is doing things that usually you find men doing. I greatly appreciate the vote of confidence...THANKSBarbey Richardson
plating shop - Lyman, South Carolina
do you have any tips for protection against hard water spots on the tanks, wheels, stainless steel, etc on my Peterbilt ? I polish the truck like chrome but I can't keep up with the spots and dulling effect.Woody jefferys
- crocker, Washington
Hello How do I bring back dull aluminum wheels? (10.00x22).They have been washed with a mild acid and neglected. The wheels are on a 1998 International. ThanksPhil Athorn
- Lunenburg, Massachusetts
To remove pits from aluminum, I usually have to start with 80 grit paper. Sometimes I have had to use 40 grit, if it is factory cast . I work my way up to 2000 grit with the finishing grain going the same direction as my intended polish grain. I first use a roughing compound and finishing up with white diamond or white tripoli. I found that hand blocking the surface produces better results compared to rotational sanding..you then would have to polish out a lot of swirl marks with the latter technique.Danny Howell
choppers - Oklahoma City, Oklahoma
Just like some of the people here have said, use a 80 or 120 depending on the scratches you made on it to get the paint out. then work your way up to 2000 fine grain. When you get to 1000 you want to do it manually by hand with water and don't press on it hard. When you sand with the 2000 use water and place a drop or two of dish detergent. this will help the sandpaper to ride smoother. DON'T CHANGE sandpaperS! use the most worn out 2000 grain you have. You will see the improvement and the dirty mirror look once it starts to dry out, but keep a little wet. I use a spray bottle with a little of dish washer. Then after all scratches are out I start buffing it with just regular Mother's Mag & Aluminum Polish [linked by editor to product info at Amazon], BOSS polishing is also good or the diamond mentioned above is also good. Do it by hand, one section at a time.
You need to have a lot of patience so it could come out right. I did my whole Suzuki frame like this and got all these tips from my brother in Puerto Rico that works on frames and rims.it will look better than a mirror if done right. If you still see some scratches after buff then go back to the last step and hit it some more with the extra fine 2000 and soap.
Good luckWilson Carrasquillo
- Fort Stewart, Georgia
April 4, 2008
I don't have access to a bead blasting cabinet but, I do to a siphon sand blaster. I seem to remember hearing somewhere NOT to use sand on aluminum. Why is this? If I start with fresh sand and regulate the pressure down, what are the problems with using this media for aluminum? The wheels have "as cast" centers that will be painted once stripped so I'm not worried about ruining the polish. Also, what do I use to mask off the sections I don't want blasted? Thanks for your advice.Chris Cook
restoration hobbyist - Lake Tahoe, Nevada
February 27, 2009
I just picked up a 1970 H0D Sportster and the aluminum engine covers are pretty dull. They don't polish out so I want to sand them to a mirror finish. How should I go about this? Thanks!Jess Wheldon
- Ramsey, New Jersey
A. Try using a 3m sisal wheel to smooth the aluminum. You can get them at hardware stores, auto parts, and Walmart. Then jewelers green rouge as the polishing compound with a cotton sewn buffing wheel. It will work good.ANTHONY KIENZLE
- SPRING VALLEY, California, USA
Ed. note: Please also see letter 800, a rather long but exceptionally good thread about aluminum polishing.