Grinders are categorized based upon the number of detachable pieces.
2 Piece – The simplest and most common grinder. 2 halves open in the middle with teeth on both interior pieces. Place your herbs in either half, put the halves together and begin grinding. When finished grinding, to retrieve the shavings pull the halves apart and tap out the herbs onto a table or rolling tray. These grinders are usually short and stout.
3 Piece – The 3 pieces are taller, cylinder grinders with a 2 piece on top to grind down the herbs and then a screw off middle section featuring either a mesh screen or storage container. The 3 piece with storage containers underneath (Cosmic Day Tripper) sell more than those with mesh screens under the grinder. The mesh screen is immediately under the metal teeth, more suited for snuff or finer grinding (not for pollen catching). The 3 piece with storage is an NHM recommended grinder for traveling.
4 Piece – The modern standard of grinders. The 4 piece cylinder has the essential 2 piece grinder on the top. The herbs then fall through to the middle collection area towards the bottom of the grinder. Underneath the collection area is a screen designed for allowing fine particles (pollen) to fall through but blocks larger plant material. The final piece is a bottom section which unscrews in order to scrape and collect the powdered pollen.
3 Main Quality Tiers – Herb grinders can be separated into 3 tiers based upon the quality of manufacturing. The different levels and prices each address a specific customer and their grinding need. The quality tiers follow in order of lowest to highest:
Plastic – cheap 2 piece grinders. These are usually given away in combo deals or sold to customers for under $10. For the low end customer. These will break or be thrown away after repeated use due to poor quality.
Generic Metal – For the budget conscious shopper. These generic metal grinders come in all the same shapes and sizes of the recognized name brands. These can work very well for what they are but will not last a lifetime as the metal is usually thinner, inferior or foreign made. Prices to customers can range anywhere from $5-50.
American Name Brands – Cosmic Case, Space Case, Mendo Mulcher – These are top of the line, proudly made in America herb grinders. They don’t get any better than these and customers pay for the quality. Each brand has its own customer loyalty and following because these grinders will last for years. No need to worry about metal shavings or chipping/scratching the finish. Prices to customers usually range between $25-100.
American vs. Foreign – A key difference between grinders (mainly for generic versus name brand) is the country of origin. Foreign metals tend to be thinner, cheaper and can scrape off during grinding. The teeth will wear out after repeated use resulting in dangerous metal shavings falling in with the herbs. American made grinders are held to higher standards and don’t see these issues.
Magnetic vs. Non-Magnetic – The top portion of some metal grinders have a magnet placed in the center creating an easy to close lid. These are harder to accidentally shake open and won’t spill your herb as easily. NHM highly recommends the magnetic grinders.
The Different Metals – Most American made grinders are some form of anodized aluminum either medical or aircraft grade.
Pollen Collectors – Pollen is the general term for the fine powder particles that pass through grinder screens. Pollen falls off the herbs during the grinding process and drops into the collection tray at the bottom of the grinder.
Pollen Presses – After enough pollen is gathered (usually a few grams), using force and heat you can compress the pollen into a super dense brick or oily disk. There are many different methods of pressing pollen. The main goal is to collect the fallen powders of herbs and press them into an extra potent and compact form.