What do I need to polish up an old set of XT crank arms?
800 and 1200 wet and dry paper, autosol and a strong right arm. 😀 or a DIY polishing kit (motorbike shops should get you one) but you'll knacker a drill doing it with a polishing kit.
Stuart
I experimented with this on some old cranks. Being lazy I experimented with removing the anodising chemically as it didn't need as much hard work and I thought it would create a better finish to start polishing from. Turns out sodium hydroxide (drain cleaner) dissolves anodising nicely and after 10 minutes in a solution of this stuff we were down to bare aluminium. I then spent about an hour with a drill and polishing wheel and compound and got the crank to a high mirror finish. I was quite delighted until I found that the crank slipped off the BB axle - presumably because I had removed material (chemically) from the crank in the important areas. In summary: looks nice but not worth the bother...
I used a bench grinder fitted with arbors, cotton polishing mops and graded polishing blocks and even that took two half days. A truly hateful job.
