Mesh screens used in the production of hash. Cannabis plant material is agitated over a series of screens with finer and finer micron grades, allowing trichomes to fall through to each successive screen, refining the product each time. Micron screens can be used when dry sifting to make kief or with bubble bags when making ice water hash.
“I finished my ice water hash with a 40 micron bubble bag.”
“What size micron screen do you use to make traditional dry sift hash?”
How to use a micron screen
The most common micron screen you’ll find is in a handheld cannabis grinder, which separates the main chamber from the kief tray. As flower is ground up, trichomes break off and pass through the screen to the tray.
This process is known as “dry sifting” and is the most basic way of creating cannabis concentrate. It is simple to do but can be extremely labor intensive on a large scale.
Large-scale dry sifting can use raw plant material, vibrating micron screens, dry ice, or other materials. Plant material is rubbed or shaken over a micron screen and the resulting product is usually put through finer and finer screens until the desired refinement is achieved.
Ice water hash uses micron screens often called “bubble bags.” Bubble bags are layered in a bucket with the finest grade on the outside and the biggest grade on the inside. Plant material is placed in another bucket with ice water and agitated. The ice water with plant material is then poured through the bubble bags and collected and dried to form bubble hash.
Micron screens and quality
Quality is measured by the purity of the final product. Common micron screens for making hash are 73, 90, and 140 microns, and the higher the number, the finer the mesh. Fine micron bags are designed to only let the heads of trichomes through. This is considered the highest quality hash and is often referred to as “Five-star” or “full melt” hash.
Screens or bags with a larger micron grade will let more plant material through, such as trichome stalks and small plant debris broken loose during agitation. This hash is less refined and of a lesser quality.