A four piece grinder does three things at once. It breaks the flower down, drops it into a chamber you can tip out cleanly, and collects the trichomes that fall through the screen underneath. This is that setup at pocket size.
Pocket size, session capacity
At 50mm across and 3.8cm tall, this is the compact end of the range. The grinding chamber takes a gram or two of flower per load, which covers a joint, a couple of bowls or a vape session. Grinding more than that means running two loads, which is where the 63mm grinder makes more sense.
How the four pieces work
The lid and the top chamber carry the teeth. Flower drops through holes in the base of the grinding chamber into a collection chamber, where it sits on a fine mesh screen. Loose trichomes fall through that screen into the bottom chamber and build up over weeks of use. Unscrew the bottom section and there is a layer of kief ready to top a bowl or roll into a joint.
Getting an even grind
Break large buds into pieces before they go in and keep them away from the center pin. Load the chamber no more than about two thirds full, close the lid and turn it ten or twelve times. Overfilled grinders jam, and the flower closest to the lid comes out in chunks. Tap the grinder on a table before opening so the last of the flower drops through.
Keeping the threads turning
Resin builds up on the teeth and in the threads, and a stiff grinder is almost always a dirty one. Every few weeks, take it apart, brush out the teeth and screen with a dry toothbrush, and wipe the threads. For a deep clean, soak the metal parts in isopropyl alcohol, rinse with warm water and let everything dry fully before it goes back together.
Specification
Pieces: 4, with mesh sieve and kief chamber
Diameter: 5cm (50mm)
Height: 3.8cm
Material: Metal
Color: Black
Capacity: Roughly 1 to 2 grams per load