# polishing crank arms



## CU155 (Mar 19, 2004)

I've got a pair of well used dura ace cranks on a race bike that I built up as my winter project. The rest of the bike looks pretty clean but the cranks are pitted with aluminum rust. It's sort of a pock mark effect. I know that I can't get all of the damage out but I was wondering what people do to clean/polish up their cranks. Thanks for any assistance.

Cheers,

Ben


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## ekdave (Sep 6, 2002)

*Any old metal polish cream or wadding*

You might want to think it over before you try this.

1. The dura ace cranks have a clear coating on them. I guess its a painted-on type of stuff or something. So when you polish with something, the polish will end up taking this protective coating off.

2. After polishing off the coating, you will find the arms buff out to a brilliant mirror shine. Start with a metal polish in a can. Some are liquids, some are like a cotton wadding type of junk.

3. Here's the part to think over.... Now they are mirror-like shiney and way cool looking. Trouble is, the protective coating is gone. Any sweat drops or road water lands on them and corrodes in hours. Leaving a yucky white corroded area.


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## brewster (Jun 15, 2004)

Once you polish, the coating is gone like he said. The good part is they look awesome....for a while. But oxidation forms and they look dull and milky looking. If you are willing to polish up with Mother's Billet aluminum polish about once a month, you can have cranks that look like chrome.


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## johndengler (Feb 1, 2005)

Check this out.

http://forums.roadbikereview.com/showthread.php?t=19274

It has some good info. and pictures on how to do such a thing. Also, it looks like you can use automotive laquer once you are done polishing to protect the parts.

-John


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## CU155 (Mar 19, 2004)

*thanks*

Thank you all for your input...anything's better than their current state. Now it's time to get out the polish.


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## neil0502 (Feb 11, 2005)

*But . . . but . .*



brewster said:


> Once you polish, the coating is gone like he said. The good part is they look awesome....for a while. But oxidation forms and they look dull and milky looking. If you are willing to polish up with Mother's Billet aluminum polish about once a month, you can have cranks that look like chrome.


But once you got them all spit-shined, couldn't you either thrown on a couple of coats of the best wax you can find (perhaps some old-fashioned paste carnauba, like Meguiars used to (still??) sell), or get some actual clearcoat through an auto repair supply shop, or . . . 

IOW: there should be a more-than-adequate way to protect these things once cleaned up, no?


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## Roger H (Feb 8, 2002)

*Polishing cranks*

I took mine to a shop that polishes motorcycle parts. Took about ten minutes to make them look great. Even took out small scratches. Cost twnty bucks (their minimum) but better than me doing it by hand.


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## Bill70J (Sep 23, 2004)

*Re-anodizing is Best*



CU155 said:


> I've got a pair of well used dura ace cranks on a race bike that I built up as my winter project. The rest of the bike looks pretty clean but the cranks are pitted with aluminum rust. It's sort of a pock mark effect. I know that I can't get all of the damage out but I was wondering what people do to clean/polish up their cranks. Thanks for any assistance.
> 
> Cheers,
> 
> Ben


IMO, once you remove the anodized finish, you will be forever polishing to keep the oxidation away, as I am not sure how durable a rattle-can clear laquer or Verathane coating would be in protecting a bare aluminum finish (especially being exposed to the elements). I think your best bet would be to polish the cranks then have them re-anodized. Or if you have a number of aluminum parts you need to work on, purchase the necessary supplies and do it yourself.


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