How do I remove paint, but save anodizing?
 

That old chestnut, you stand on a box to grab an item off your top shelf, a different box crashes down lands perfectly on a can of blue spray paint, lid off.

the paint sprays on some gold anodized brake levers that you just bought on eBay.

paint also got all over tools, but I’m not worried about blue paint on the blue handles of park tools.

what’s the secret to removing the paint but saving the gold?

https://cimg3.ibsrv.net/gimg/bikefor...d5ea96efb.jpeg
Gosh darn. Of all the colors in the world.
https://cimg8.ibsrv.net/gimg/bikefor...294ccf269.jpeg

I wouldn't think acetone would harm anodization, but best to do a test first.

I'm shocked you even own blue spray paint.

As long as your stripping agent is not sodium hydroxide, your anodizing should be fine.

I've used acetone and lacquer thinner to remove paint from anodized parts with no issues.

Any solvent shouldn't affect anodizing.

Yes acetone or lacquer thinner should work but if not, use paint stripper. None of those affect anodizing.

all good advice^ and to state what may be obvious: resist using something abrasive (such as a 3M scratchy pad or steel wool) to apply solvents and wipe off that paint.

"Anodizing" is simply (artificially "thickened" and colored) aluminum oxide which forms on pure aluminum surfaces naturally when exposed to air (but much thinner and with no rainbow colors).
Anything harder than aluminum oxide WILL scratch an anodized finish if abraded...don't ask how I know... and don't reach for the newest version of a household dishwashing pad (green) which now come "reinforced" with hard metal bits!

The dyes used to color AL-oxide anodized finishes are nearly all affected by exposure to the UV in sunlight, so will fade. Black anodizing is especially susceptible to fading and it happens the quickest of all colors. Interesting to see what color dye was the "basis" for a particular "black" dye: it can be purple, brown, gold or sometimes green, all made as dark as possible so when fresh it appears to be black

Yeah though some black ano lasts longer than others. I've seen some Art Stump ano parts from the 70s that are still nice and dark to this day. These '70s Universal 68 brakes were still fairly dark when I sold the bike ~10 years ago.

https://cimg6.ibsrv.net/gimg/bikefor...e1d611fa58.jpg
https://cimg7.ibsrv.net/gimg/bikefor...ceb3746525.jpg
Maybe starting to look a little purple?

I'm guessing there are differences in the actual dye used, but also in the thickness of the ano and how it was sealed after the dye job. Just guessing though.

Red also seems especially prone to fading in sunlight. My blue Modolo Professional brakes from 1980 appear to be as rich and dark a blue 45 years later as on day one. I'm not normally a fan of color ano because it looks terrible when scratched or worn thru to the alu below, but I am fond of those Modolo brakes for sentimental reasons.

Just strip the gold and have them anodized blue, problem solved. :roflmao2:

all true and a good guess that dyes used and the sealing (a critical last step in the process) will all have an effect on how well the colors age. These old Universals are trending toward "purple" but still points to very good anodizing done to them BITD that they lasted this long.
Could be there were different (maybe more toxic?) dyes available back then or they just spent more time than typical these days (my turn to make guesses).