My Shimano crank arms are looking a little worse for wear with the black anodizing looking very patchy. I have a suspicion that they would look fab if I could strip it off and polish up to a mirror finish. Someone must have done it, is it one of those jobs that you wish you had never started or are good results relatively easy? Would love to see pics too please.
Polishing crank arms wink wink nudge nudge
I've not done it, but my 'naked' Race Face cranks still look pretty much as good as new after a year or so's riding.. my painted anodised cranks do not!
I think I've seen photos of polished XTR cranks knocking about...
I've done it, you'll need a polishing kit plus a plug in electric drill for the high speed necessary. It takes longer than you think and mines scratched alot now with the weather we've had. I will helitape mine next tithe it I may get them re-anodised.
Never polished a set, but my mate was pissing about doing his one night and decided to set to mine with some caustic soda. It strips the anodizing off very easily, then you could just polish them up a piece of piss afterwards.
Loads of methods to do this.
Firstly you should remove the old anodising, a mild caustic solution should do, I've used industrial cleaner but some people use things from drain unblocker to oven cleaner.
Next is to polish. Again several methods. You can use emery paper and decrease the grit size or you can use scotchbrite pads and polishing compound or go the power tool route and buy some mops and compounds.
Have you any gouges or heavy scratches in the cranks?
Here are some I've done.
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YK they all look lovely, which method did you use?
If they're a smooth/shiny black ano finish, caustic soda (drain cleaner crystals) will take off the anodised layer and a buff with a polishing wheel on a drill with some t-cut will shine them up nicely. If they're a sand-blast anodise finish it'll take hours with wet and dry paper to get them smooth. Also don't be seduced by the just-finished pics too much, after some use they fade and look good, but not quite so pimpy. I did a set of M760 XTs and I'm happy with the result but it's more a wet-weekend project than something I'm in a hurry to do again, unless I can find a drill attachment to speed up the wet-dry sanding stage.