Your grinder is harder to turn than it used to be, the herb gets shredded unevenly or stays stuck in larger chunks – many people immediately think of blunt teeth. But is that really the problem, and can you even sharpen a grinder at all? We explain what's behind the drop in grinding performance and when cleaning, repairing or a new grinder is worth it.
Why a grinder becomes "blunt" in the first place
The teeth of a cannabis grinder are usually milled or cast from aluminium, zinc or stainless steel – a solid, diamond-shaped profile that can't be compared to a knife blade. Unlike a blade, this profile hardly wears down with normal use. What feels like bluntness is, in the vast majority of cases, not material wear but resin and kief residue that builds up between the teeth and on the thread, blocking movement.
Gummed up or genuinely worn? How to tell the difference
A gummed-up grinder turns stiffly or jerkily, but moves easily again after cleaning and then grinds just as finely as on day one. A genuinely worn grinder shows different signs: the teeth look visibly rounded or have lost their edges, the herb gets crushed coarsely and unevenly instead of cut despite the grinder being clean, or the thread between the halves is worn out and noticeably wobbly. Only in the second case will cleaning alone not help.
Cleaning: the first and usually only step you need
In most cases, a thorough clean is all it takes. Take the grinder completely apart and soak the metal parts in high-strength isopropyl alcohol for 20 to 30 minutes – longer for heavily resinated models. Afterwards, residue comes away easily from the teeth and thread with an old toothbrush or a soft wire brush. If you don't have alcohol to hand, you can also put the disassembled grinder in the freezer for an hour: the resin becomes brittle and can then be knocked off with a brush. Once dry, the thread usually turns like new again.
