Micron bags are essential for a clean and effective pressing process. Selecting the correct pore size (measured in microns) can significantly impact the colour, flavour, yield, and the risk of bag blowouts during extraction.
What Is a Micron?
A micron is a unit of measurement equal to one-thousandth of a millimetre. In filter bags, micron size refers to the distance between the threads in the mesh. Smaller microns mean a finer mesh, ideal for capturing small particles, while larger microns have coarser textures for handling bulkier material.
Small Micron Bags: 5µm – 50µm
These sizes are best for pressing refined material such as dry sifted or sieved plant resin. Fine particulates can range from approximately 25µm to 160µm in size, so smaller micron bags (like 5µm to 37µm) are ideal for containing the material and preventing loss during pressing.
For example, 25µm bags are a common sweet spot—fine enough to retain delicate material, while still allowing for a clean extraction
Mid-Range Micron Bags: 75µm – 160µm
Mid-sized micron bags are typically used when pressing more fibrous plant matter. These pore sizes prevent unwanted solids from contaminating the final product while still allowing oils and resins to flow through. They offer a good balance of yield and cleanliness.
These sizes are also suitable for filtering slurries like those found in ice water extractions or similarly washed material, though not necessarily for pressing that same material unless refined further.
Platinum-stitched bags in sizes like 160µm or 25µm are commonly paired with billet-style pre-press mold to help compact the material and increase pressing efficiency.
Large Micron Bags: 220µm
Large micron sizes are used primarily to add structural support and prevent blowouts—especially in setups involving double-bagging. These bags help control expansion and reduce pressure strain on finer bags nested inside.
For instance, stitch less "bulletproof" bags in the 220µm range are engineered for rigidity. These are particularly helpful when pressing very fine bags (e.g., 25µm) that tend to stretch during high-pressure applications.
Pressing Tips for Best Results
1. Start with High-Quality Material
Your final extract is only as good as the material you begin with. Whether you're working with sifted powder, dried flowers, or other plant forms, quality control matters—proper storage, humidity, and cleanliness are key.
2. Match the Micron Size to Your Material
- Smaller Microns (5–50µm): Best for fine, refined material. Yields may be lower, but quality and clarity are typically higher.
- Larger Microns (75–220µm): Better for unrefined or bulkier material. Yields increase, but the extract may carry more plant matter.
3. Use New Bags Each Time
Though it's possible to reuse filter bags, it increases the risk of tearing or blowouts and reduces consistency. Always using a fresh bag helps ensure cleaner results and more accurate outcomes.
You can perform a second press on a spent bag for additional yield, but the result will contain more particulates and is generally better suited for non-consumable applications like balms or infusions.
