Rubbing alcohol and salt should do the trick. Never tried it on my grinder(haven't had to yet), but works great for pipes and bongs.
i second this works for all my pipes bongs and grinders i just put salt in alcohol in them and shakeThe best way to clean any pipe, grinder or bong.
ingredients
-alcohol
-course salt
to clean a BONG, poor a few oz in a bong and a tsp of salt swish around, watch resin come right off
to clean a small pipe or grinder, poor a few oz of alchahol in a tupaware with a lid add salt. try to get salt inside the pipe, close lid and swish gently
the alcohol breaks down the resign and the salt helps scrub,
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