FAQ on How To Select Rosin Filter Bags

Do I Have to Use Filter Bags When Pressing Rosin?

Using a filter bag or not is very personal matter, and it depends on your own preferences. If you don’t mind getting a final product that is mixed with essential oils and plant particles, you don’t have to use a filter bag. Rosin pressed without a filter bag will taste more like regular smoking. However, if you want to experience better quality dabbing, than we would advise you on using mesh bags. In addition, you should be aware of that, when pressing with a filter bag, you may experience a slight loss in yield, which means ultimately you have to decide for yourself what matters to you most, quality or quantity.

What Kind of Filter Bag Material Should I Use?

You can find nylon, metal, polyester, and silk filter bags on the market. The best material for filter bags is nylon. It is heat resistant, durable and stretches up to 40% under pressure. Stainless steel mesh can easily scratch the surface of the platens and eventually damages them. Polyester thread bags tend to blowout due to the fact that they shrink with heat, and silk is prone to blowouts since it doesn’t stretch the way nylon does.

How are Filter Bags Measured?

There are two important parameters: mesh size and bag dimensions. Filter bags are made of a mesh material, and mesh size is measured in microns. The smaller micron size, the tighter your mesh is. For example, 90 micron mesh has larger holes between the threads than the 36 micron one. The physical bag dimensions matter, too, since you have to choose the bags that closely fit your press plates. For example, for 3 by 5 inch plate press, you can choose 2 x 4, 3 x 4, 2 x 6 filter bags.

What Mesh Size Should I Use?

The general rule is the finer precursor, the tighter mesh you can use. A precursor such as kief, dry sift, or bubble hash when heated and pressed flows easily; this type of material can be used with fine meshes. Flower, trim, and shake contain a lot of material that traps and prevents the pressed extract from easy flowing and, thus, they require a looser mesh bag. Here are our general recommendations which you can use as a starting point for trying filter bags:

Mesh Size
160 120 100 90 72 36 25
Flower / Trim The best yield with decent quality Excellent yield with good quality Great yield and quality Great yield and quality Good yield with excellent quality Decent yield with the best quality
Kief / Bubble Hash The best yield with good quality Good yield with the best quality Good yield with the best quality


How Do I Use the Bags?

First, turn your bags inside out so that the seam is inside. Then break up larger pieces and fill the bag evenly with your material. Make sure it is not overfilled and stuffed to the edge of the bag. Fold the edge of the bag to prevent the material from falling out of it. If the filter bag is too long, you may need to trim it to remove unused mesh that may trap extract. Pre-pressing your precursor to create an even thickness puck also helps.  The overall thickness of the filled bag shouldn’t be more than a quarter inch.

How Do I Make Sure The Bags Don't Blowout?

Do not over-stuff your bags with material. Most blowouts happen for this same reason. Use about half of an ounce of flower per one 2.5 x 4.5 filter bag. Another tip is don’t apply too much pressure at once. Proceed slowly. This will allow for air and pressed extract to be squeezed out the bag instead of becoming trapped inside it and causing the blowout. Using pre-press molds also reduces bags blowout since pre-pressing removes extra air and makes your precursor of equal thickness, which in turn helps to apply the pressure equally to all parts of the material for better yield.

Can I Reuse My Filter Bags?

Yes, you technically can. You can try to clean them in rubbing alcohol and then wash with soap and water to remove as much of the leftover debris as you can. However, be aware that the filter bags mesh will still have remnants of material from the last press. In addition, the mesh will be stretched out and thus more prone to blowouts.