If you make coffee regularly, grinder should be cleaned at least once a week. Let share grinder cleaning techniques in this topic.

Before I start cleaning, I empty the grinder of any beans or grinds. Then I take off plastic reservoir, wash it and dry thoroughly. With a brush I dislodge stuck grounds and oils from the burrs.

I also use a dry paper towel to rest oils and grounds that still remain in grinder after I cleaned it with the brush.\r\n\r\nDo make sure the burrs do not get wet after cleaning, because this could cause rusting.

Since I grind exclusively for espresso I clean mine every 1/4 lb. or so, which equates to 2-3 times weekly. I like to use a vacuum cleaner to do so. I also use a small toothbrush to lightly scrub the grinding chamber and burr teeth. Every now and then I also wash the bean bin and grounds bin in hot soapy water, let dry and use. It might not be important for some brewing methods, but absolutely essential for espresso. Later!