hard to see if it is the right bit - give them a ring and check. This is not what i saw this week but it might be close. If i can remember the other site i will get back to you.
I have some black ones if your stuck. Mine might be Bakelite though
Probably plastic :?
I havent taken this to anywhere near 12000 grit but im happy the heavy scraping has been removed from the edge and across the logo. The knuckles came up quite well also.
Must say i prefer polishing cranks rear mechs have lots of tricky places.
On that note one of my next clean ups is a nice early Suntour V-GTluxe. Dear lordy, seen the amount of parts that make one up :shock:
Edit: Suntour pic added
Attachments
Shimano FD-A105 Golden Arrow Rear mech 004 (Medium).webp
This is a bit more heavy duty than small bicycle parts but here is an alloy wheel I polished last year
Wheel as purchased
I removed the powder coating using 400 grade sandpaper on an air powered DA sander, then using 400 grade wet & dry I cleaned up the bare wheel face, then 1200 grade wet & dry to give a finer finish and eventually finishing with 2000 grade wet & dry.
I start to polish up the wheel using Solvol Autosol and the results were encouraging although not as good as I needed, so I spent another hour with the 2000 grade wet & dry to get a really smooth finish.
Click images for full size
This is the tiny marks that had be sanded out
The aim is to have a uniform even finish
Once prepared it took a maximum of 10 minutes to polish the wheel using the rotary and 10 minutes to finish by hand
The finished results are rather good considering
The alloy used in wheel making is not completely smooth, so a complete mirror finish would be almost impossible, plus if it was a mirror finish the lacquer would not adhere to it properly, so I am happy with my efforts. Just need to get it to the paint shop now for the painter to do his bit.
Next was to have my local car body repair shop etch prime, clear lacquer and over dry the wheel to protect it from the elements
I have a 3 phase compressor that puts out 24CFM of air so I can run virtually any tool I require. For these wheels I used a DA sander to remove the hard powdercoat layer and most of the blemishes. I used an electric rotary polisher to buff up with Autosol and the rest was done by hand.
The problem with alloy wheels is the alloy is extremely tough, much tougher then bicycle parts and the wet & dry wears out long before the blemishes are removed so you need a plentiful supply of W&D and change for a fresh piece every few minutes