# buffing out scratches on crank arms



## moschika (Feb 1, 2004)

i just got a crankset off ebay and the crank arms are a bit more scratched up then the pics showed. the description said there was some scratching on the crank arms but there are more then i thought there would be.

can you buff these scratches out or down? if so how would you do this? none of them appear particularly deep.


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## C-40 (Feb 4, 2004)

*it will remove the aonodize...*

Scratches can't be removed without also removing the anodized finish in the area where the polishing is done. Once the anodize is removed, the finish will not match the rest of the crank and it will tarnish. Polishes like Mother's or Semichrome are too gentle to remove scratches. They are intended to remove tarnish to keep a polished surface bright.

For info on metal polishing, try this site: http://www.swmetal.com/

Metal polishing products can also be purchased at home depot and lowes.

The alternative is to completely remove the anodize and polish both crank arms. With home equipment, it could take a few hours.


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## lithiapark (Apr 6, 2003)

I have crankarms that are anodized, some that are just polished, and some that are polished and clear coated. The polished type would be easiest, some 2000 grit wet sandpaper and Mothers magnesium/aluminum polish should do it. You might have to start with coarser paper and work to finer depending on how deep the scratch is. Clearcoated or anodized parts would probably have to have all the anodizing/coating removed to get it to look the best and there are ways to do that. http://www.caswellplating.com/index.html is a company that sells all sorts of material to do buffing/polishing, and they have a good section on how-to.


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## unchained (May 8, 2002)

*Oven Cleaner*



moschika said:


> i just got a crankset off ebay and the crank arms are a bit more scratched up then the pics showed. the description said there was some scratching on the crank arms but there are more then i thought there would be.
> 
> can you buff these scratches out or down? if so how would you do this? none of them appear particularly deep.



I was researching this at google groups. Oven cleaner will remove the anodizing. For polishing bare aluminum, I have gotten excellent results from the newer, more expensive Mothers product.

If the scratches are not too bad, you could try a Scotch Brite Pad and water. I used the new non-scratch variety of the pad on an anodized stem and handlebars with good results.


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## Dave Hickey (Jan 27, 2002)

unchained said:


> I was researching this at google groups. Oven cleaner will remove the anodizing. For polishing bare aluminum, I have gotten excellent results from the newer, more expensive Mothers product.
> 
> If the scratches are not too bad, you could try a Scotch Brite Pad and water. I used the new non-scratch variety of the pad on an anodized stem and handlebars with good results.



Ditto oven cleaner. It works good for removing anodizing. Extra strength Drano works great too. Just be careful....


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## Roger H (Feb 8, 2002)

*Polishing cranks*

I took my Dura Ace cranks to a shop that polishes motorcycle parts and such. Cost me twenty bucks but they look excellent.


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## cdhbrad (Feb 18, 2003)

*They look great. You can barely buy the compounds*

and buffing wheels for $20, much less the time you saved. I will keep that in mind for some I need touched up.


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