Acetone cleans anything. =)
(it also leaves acetone-residue of unknown composition.)
i probably used some unholy amount of acetone, like 5 litres, for cleaning glassware last year.. but it's phat, because it dries really fast. (oh, but remember always to rinse things with the solvent you're going to use)
none of that has anything to do with cleaning out additives.
first- i am not sure if this works for coke, but it probably will work for meth.
(i'm only answering this because yer a mod) =)
roches' guide to acetone
acetone (aka dimethyl ketone or 2-propanone, which is the only possible propanone, but i'll call it 2-propanone anyway) is a polar aprotic solvent that dissolves pretty much anything.
but for some reason, it doesn't dissolve meth (HCl) very well, although it *does* dissolve most of the possible fillers. unless the filler is something wack (something that isn't really soluble in *anything*), then it should dissolve in acetone.
the *proper* technique is to wash the filter cake with few portions (an absolutely minimal amount) of ice-cold acetone during vacuum filtration, but since you probably can't do that you'll have to think of something else.
you have to use COLD acetone, as cold as you can get it. that is the main thing. it has to be COLD, and you don't need much. since the cut was probably added to powder you probably dont need to crush anything further... anyway, you should be more concerned about toxic synthetic byproduct impurities than cuts.. which will be present in a very small amount. try to do it on filter paper, but just, make sure you don't use much acetone and that it's VERY COLD.
btw.. obviously you can evaporate the filtrate if you think your yield is low.