Feeling lazy to open your grinder to clean it inside?
Yeah, me too.
So, I started using some uncooked rice to remove the old grinds. So, I would load about 10-15 g of rice, grind it away, and then polish everything off with a vacuum cleaner. And all went happy, for a while.
Until one day I opened the grinder, and saw some rice grinds that stuck to the burrs. That was the leftovers of the rice that I cleaned the grinder with a couple of weeks ago!
So, the conclusions here:
1. Rice (or any commercial product for that matter) really cannot
the old grinds.
2. What's worse, it looks like the rice grinds cannot be completely pushed out by the new coffee after such "cleaning" either.
3. The best was to go with the cleaning is to vacuum the grinder from time to time (I tend to do it weekly), and then once in a while to open it, and clean with a brush.