🇺🇸 Retired veteran, father, rock-climbing expert & rosin connoisseur.
Bubble wash bags, rosin filter bags, and dry sifting screens are various types of filters that allow extractors to mechanically separate pure, unblemished cannabis resin from the cannabis plant. It’s thanks to these nylon filters that we can collect high purity cannabis concentrates without the use of solvents.
Solventless cannabis extracts exist in a variety of premium forms, including bubble hash, rosin, and dry sift. Thanks to quality bubble wash bags, rosin filter bags, and dry sifting screens, extractors can create an assortment of extracts depending on their production objectives.
But using filters that lack micron accuracy can dash the quality of extracts produced. Micron accuracy is an important consideration for extractors who strive to create the cleanest, most potent solventless extracts available.
What Do We Mean By Micron Accuracy?
Micron accuracy refers to the exactness of the pore size across an entire nylon filter.
Each type of filter, whether it’s a bubble wash bag, rosin filter bag, or dry sifting screen, contains tiny holes designed to sieve starting cannabis material. These holes, or pores, allow tiny particles of cannabis matter to pass through, while capturing pieces of material (including trichomes) that are as large or larger than the pores.
In bubble wash bags and rosin filter bags, the size of these pores are measured in microns. Microns are one of the most important measurements and differentiators in solventless production.
Note that in dry sifting screens, pore sizes are measured in Lines Per Inch, or LPI. We’ll touch on this again later, but the concepts that apply to microns equally apply to LPI.
Why Is Micron Accuracy Important?
Full, mature trichome heads are the keepers of the cannabis plant’s greatest treasure. The highest concentration of therapeutic compounds that the cannabis plant produces, namely cannabinoids and terpenes, are found within trichome heads. These trichomes grow in copious amounts on the flowers of the female cannabis plant.
Micron accuracy allows us to target only these trichomes and separate them from the rest of the cannabis material used in extraction. If a filter is rated as 90-micron, it’s important that the pore size is in fact 90 microns across the entire surface area. This ensures that the material captured by this filter is the predictably the same size throughout.
Bubble Wash Bags
If you’re at all familiar with ice water extraction and the process of using bubble wash bags to make hash, then you’re familiar with the importance of filters and microns. Bubble wash bags are an extractor’s main tool used for separating full, mature trichome heads from cannabis flowers and trim leaves.
Bubble wash bags are measured in two ways, by volume and filter size. The total volume of bubble wash bags is measured in gallons, which generally matches the size of the wash vessel you’re using.
The other way that bubble wash bags are differentiated is by filter size. Full bubble wash bag sets include 220, 190, 160, 120, 90, 73, 45, and 25 micron filters.
The closer the filter pore size matches the size of full, mature trichome heads, the more pure the hash collected from that wash bag will be. The best hash is generally collected from the 90, 73, and 45 micron bags.
Accuracy in microns is important to ensure that the pore size is consistent throughout the entire filter. Variation in pore sizes leads to a variation in size of material that the filter catches. For example, if the screen is stretched or deformed and the microns are not accurate throughout, it may be catching only trichome heads in a certain area of the filter, while another area is catching trichome heads in addition to larger pieces of plant material.
Micron inaccuracy directly impacts the quality of hash in a negative way.
Lower-quality bubble wash bags tend to stretch and warp over time, which creates distortions in micron accuracy. This is one key reason why it’s so important to use high quality bubble wash bags for hash extractions.
Rosin bags are made of the same type of food grade nylon filter that’s used in bubble wash bags. The process of pressing rosin is completely different from the process of ice water extraction for making hash, but filters are central to both forms of solventless extractions.
Extracting rosin involves pressing cannabis material, either dried flowers, bubble hash, or dry sift, between heated plates at high pressure. The heat and pressure cause trichomes within the cannabis to rupture, thereby liberating the resin inside to liquefy and flow out as rosin.
Rosin bags act as filters, containing the starting material and preventing excessive contaminants from mixing with the rosin. Plant particles plus unwanted oils and fats are captured by rosin filter bags, purifying the rosin as it’s extracted. Different types of starting materials call for different filter sizes. The right size filter, measured in microns, provides effective refinement while allowing for maximum yield. For example, pressing cannabis flowers requires rosin filter bags with larger a pore size, like 90 microns. Pressing a more refined material, like bubble hash, requires smaller pore sizes, such as 15 or 25 microns.
Read more about how to choose the right rosin filter bag in the article What Micron Do I Use?
The accuracy of microns in rosin filter bags is critical to producing a consistently high-quality solventless extract.
Dry Sifting Screens
Dry sift is the third main category of solventless cannabis extracts. Dry sift is made by sieving dried cannabis material through a series of nylon filters called sifting screens. The mechanics of separating trichomes from cannabis to make dry sift is similar to the process of making bubble hash, just without the ice and water. While bubble wash bags containing nylon filters of various micron sizes are ideal tools for ice water extraction, flat, tightly-stretched screens inside wooden or aluminum frames stacked one on top of the other are perfectly suited for dry sifting.
Extractors sweep dried cannabis back and forth across the surface of the upper screen in the stack, allowing trichomes to break free from the material and fall through the series of filters. Each screen collects a different grade of dry sift. Although dry sifting screens are measured in LPI, it’s the same concept as filters measured in microns.
The screen containing the pore size most closely matching that of full, mature trichome heads collects the highest quality of dry sift.
If the nylon screens warp and stretch over time, the pore size may become distorted. The pores in one area of the sifting screen may not exactly match the pores in another area. This will result in uneven performance across the screen, as the varying pore sizes allow different sizes of material to pass through.
This can result in catching excessive contaminants in your “keeper screens”, and potentially letting valuable trichomes fall through.
Micron accuracy and consistency throughout a filter impacts every type of solventless extraction. Filter bags and screens that have pore sizes true to their advertised micron allow extractors to dial into various grades of quality.
In general, the filter most closely resembling the trichome head size in any given batch of material is the filter that will produce the highest quality concentrate.
Extracting the highest purity of hash requires consistent and accurate pore size throughout a filter. This is why micron accuracy is so important.
Purchasing high quality bubble wash bags, rosin bags, and sifting screens is worth the investment. Premium materials and solid construction lends itself to better accuracy and results over time, worthy goals of any solventless extractor.
What are your thoughts on micron accuracy? Let us know in the comments!
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FREQUENTLY ASKED QUESTIONS
What is micron accuracy?
Micron accuracy refers to the exactness of the pore size across an entire nylon filter.
What are microns?
In bubble wash bags and rosin bags, the pore size in these filters are measured in microns. Microns are one of the most important measurements and differentiators in solventless production.
Why is micron accuracy important?
Micron accuracy allows us to target only the trichome heads, separating them from the rest of the cannabis material used in extraction. If a filter is rated as 90-micron, it’s important that the pore size is in fact 90 microns across the entire surface area. This ensures that the material captured by this filter is the predictably the same size throughout.
What happens when microns aren't accurate?
Filters with inaccurate microns throughout will capture different sizes of material, potentially allowing increased contamination into the concentrate.
How can you ensure micron accuracy?
Investing in high quality bubble wash bags, rosin bags, and dry sifting screens is the best way to ensure micron accuracy.