TromboneChat

Is it possible to remove acid bleed from a raw brass bell? If so, how?

You can buff it off with brass polish. If the bell is lacquered, the acid bleed is under the lacquer and not easily accessible. Note that if the acid bleed is very black it can be very deep into the brass -- if it doesn't come off easily don't get aggressive.

You might also want to bathe the bell in a solution of sodium carbonate (baking powder), about 3% by weight in water. Follow that with a good wash. That will neutralize any acids still in the bell rim that can cause recurrence of the acid bleed.

Good points. This is why I'm scared to buy new horns anymore. I have been lucky with my new horns but I prefer one that is at least a decade and if it doesn't have acid bleed it's probably not going to get it.

Acid bleed has potential to occur on any bell that has a soldered rim, regardless of brand, and to some extent, age. On a raw brass bell, it wouldn't be acid bleed, as such, and can be polished away fairly easily. On a lacquered bell, it can be corrected, but that would require a full refinish of the bell for best results. There is also no guarantee that it will not re-occur in the future.

Bach42t wrote: ↑Wed Dec 16, 2020 11:30 am Good points. This is why I'm scared to buy new horns anymore. I have been lucky with my new horns but I prefer one that is at least a decade and if it doesn't have acid bleed it's probably not going to get it.

Huh. I buy really old used horns... a lot of them still have acid bleed. I have never done anything about it and don't care to start now. It usually progresses a bit and then stays that way forever. At least, it's not growing anymore on the 50/60 year old horns downstairs...

Cheers,
Andy

Humidity may play a part in the onset of acid bleed. I keep some silica gel packs in my cases, and so far, so good!!