Parts like sprockets, chains, hubs, BBs, etc are quite useful for projects to build tools, furniture, art. I get them at no cost by dumpster diving. Cleaning them is quite a pain though. These are some of the options I’ve considered:

• dishwashing machine— if normal dishwasher detergent is used, I would expect it to corrode aluminum parts (correct? Can someone confirm or deny that?) Chains and /some/ sprockets are steel, right? Would they do well in the dishwasher? I wonder if there is some kind of alternative detergent that won’t harm aluminum since I always have to hand-wash an aluminum pot cover.

• ultrasonic bath— this method strikes me as the most convenient and what I would expect someone who needs to clean lots parts to use. But there is a risk of de-anodization if you use degreaser. Some jewelers use ultrasonic cleaners with a cocktail of Mr. Clean and ammonia. Would that work well on bicycle parts, non-destructively?

• Enzyme-based oven cleaner— I tested this on sprockets and it seemed to work quite well but doesn’t get into the nooks and crannies and dissolve any of the mud.

• Enzyme-based drain cleaner— instructions say wait 6 hours, so i did not test it. Is that time perhaps just because it takes that long to spread down the drain and munch on large volumes of gunk? Perhaps it would work in less time on bicycle parts.

• boiling water with dish soap— I hoped it would melt the greasy grime. The water was quite dirty afterwards but did not make much noticeable progress.

• degreaser spray— did not test this. I just have degreaser for kitchen surfaces so maybe not the right stuff.

• bicycle cleaning spray— kind of strange that this exists. Bicycles have many different materials and different kinds of grime. It did not do too well on greasy sprockets as far as I could tell.

Question on the enzyme-based cleaners: enzymes are a bit pricey by volume compared to other cleaners. Is there a way to store and reuse them? Ideally I would like to pour a bottle of enzyme-based drain cleaner into a bucket and just always soak parts in that same bucket. Do those little guys multiply when you feed them? If the water is always dirty, will the enzymes always be too full to chow down on parts being added?