🇺🇸 Retired veteran, father, rock-climbing expert & rosin connoisseur
Whether you’re new to pressing or looking to improve your current levels of quality and yield, this short guide will help you understand the importance of using bags when pressing rosin and how to determine the right bag for your setup.
A rosin bag is used to hold cannabis flowers, kief, or bubble hash while being pressed between heated plates. Rosin bags provides a barrier through which rosin separates from the source material, which leaves a final product that’s free from impurities.
Rosin bags are also used to achieve a more consistent density within the packed flower, kief, or hash so that rosin can flow freely from your material and onto the parchment. Working the rosin bag and contents between your fingers, you can work out any inconsistencies or small gaps in your source material by eliminating pockets between pieces of flowers. This consistently packed material will optimize your rosin yield.
Additionally, cannabis can be pressed without rosin bags, however you’re likely to have tiny particles of plant material included in your rosin. As heat and pressure between the plates causes cannabis trichomes and terpenes to liquefy, bags ensure only the good stuff is squeezed out and that your source material stays contained and separated from the rosin.
Although rosin bags all serve the same purpose, they are not a “one size fits all” product. The main things to consider when choosing the right bag are material, microns, and dimensions.
WHAT ARE ROSIN BAGS MADE OF?
The best material is food-grade and boil resistant, allows for a bit of flex under pressure, and is pliable enough to easily work with. Although there are nylon, silk, and metal bags available, only nylon makes the grade. Silk doesn’t flex and is therefore more prone to blowouts, and metal screens can damage your plates. Nylon is the ideal material for pressing rosin.
WHAT IS A MICRON?
Next to consider when choosing a rosin bag is the micron size. What is a micron? A micron is a unit of measurement that equals 1/1000th of a millimeter, and can be visualized as the size of the gaps between interwoven threads of the screen. As the contents of the bag are put under heat and pressure, how much and what quality of rosin that’s forced through the barrier is largely determined by the micron you’re using.
So how do you decide? The micron you’re looking for depends on the material you’re pressing
Size ranges from 25 to 120 microns. For pressing rosin, 120 microns is the largest size you’ll generally consider, since cannabis trichomes are 120 microns in diameter (if not a bit smaller).
• Flower = 90 microns or greater
• Dry sift or kief = 25-90 microns
• Bubble hash = 25-45 microns
Consider source material on a spectrum from least refined (flowers) to most refined (bubble hash). As the source material gets more refined the optimal micron size will get smaller and smaller. Bubble hash requires the smallest micron size, while flower requires the largest.
Greater spacing between interwoven threads in the screen allows more material to pass through, which is necessary with flower. However, using microns too large may allow dust and plant particles to escape the bag. Generally speaking, the smaller the micron the purer the rosin, as long as you’re staying within the appropriate range.
ROSIN BAG SIZE
How big are your plates? How much source material are you looking to press at once? A fully-packed rosin bag should fit well within the parameter of your plates and include about one inch of extra material at the top of the bag, which should be folded over to keep material from squeezing out of the top.
If you have a lot of material you’re trying to press, then you want to buy the biggest bag that will still provide at least a one-inch buffer between the edges of the plates and the edges of the bag. The one-inch buffer will ensure consistent temperatures in the material at the very inside all the way to the outside edges of the bag.
If you’re just pressing a few nugs, 1.5in x 4in bags should work nicely.
For the fastest and most efficient way to produce pure, high-quality rosin, be sure to choose the right rosin bag for the job. Remember to take into consideration the proper micron for the source material you’re squeezing, the material from which the bag is constructed, plus the size of your plates and how much material you plan to press at once.