residue

[lewis1641]

when i strip annodising off with drain cleaner i am left with a matt black residue on the aluminium part. what is it?

 

[Tallpaul]

Possibly just oxidation of the alloy. Does it buff off with Autosol?

 

[lewis1641]

it needs 1200 wet and dry then autosol.

it actually looks quite cool though!

 

[memyselfandi]

Was the part black by any chance? Like the other guy said it's probably just oxidation. and maybe the anno its self.

Any chance of seeing a pic of how it turned out?

 

[lewis1641]

i'll popst a pic.

the cranks were indeed black but red stuff i've done went black too

 

[kaiser]

You've left it on too long, try scrubbing with a wet hot soapy brillo pad after the oven cleaner. Keep it moist, when it dries, its harder to get off and it'll dry quickly.