Wondering what the right type of bag you need for your rosin heat press?
We’ve put together a comprehensive guide to help you make the right decision when it comes to buying the right bag for you. This includes the type of bags, why you need one as part of the extraction process, and ultimately how to make the right choice for the type of press you own.
What exactly are rosin press bags?
Put simply, they are an essential part of rosin pressing, or removing the cannabinoid oils from the cannabis plant.
They are bags, similar in some ways to tea bags or coffee filters, that act as filters to keep plant material from getting into the oil that is removed. Rosin bags are typically made from nylon mesh that is sewed together to create a rectangular bag. And if you’ve found the right rosin press from our guide, then you’ll need to seriously consider the types of bags that will go with your new pressing unit.
They can come in a variety of sizes and micron units, which measures how fine the grate in the bag is. To use a rosin press bag, you first have to turn it inside out, then you simply break whatever material you’re using down, put it inside the bag, and fold over the bag to keep everything inside.
Factors to Consider Before Buying Rosin Press Bags
- Micron units: Rosin press bags usually come in a range of 25-180 micron units. The lower units are better for pressing fine material, like dry sift or bubble hash. Higher units are used to press cannabis flower or trim. The unit will also affect how well your rosin is filtered and the yield of your final result. Lower units filter better, but usually result in lower yields, while higher units have higher yields but don’t filter as well.
- Size of the bag: You’ll want to make sure you buy a size that is compatible with your rosin press plate. If you have a 2”x5” plate, you won’t want to buy a bag with a width of 3” because it won’t fit. Also keep the size in mind when filling the bags, as you don’t want to overfill a small bag. This could result in blowouts if you’re not careful.
- Material: You can buy press bags that are made from silk or use metal screens, but it’s generally agreed that nylon is the best material, as silk can be less durable and metal screens can result in lower quality rosin that contains a lot of leftover plant material. You’ll also want to see if the bag is made from 100% nylon, since those bags are going to be higher quality that ones made with other materials mixed with the nylon.
- Dyes: I’d say I’m not alone in preferring my bags to be dye free, since I’ll be ingesting the oil I press out of them. You don’t want any dye leaching into your product, as that’s going to be harmful to you or anyone else who ends up using the rosin.
- Solvent-Resistance: Do you want to be able to wash and reuse your bags? I personally wash them with rubbing alcohol, so I need a bag that is solvent resistant. If you don’t care about reusing bags, then this isn’t going to be a big deal to you.
- Pressure tolerance: If you prefer to use higher amounts of pressure when pressing your rosin, you’ll want a bag that can withstand that pressure. Be sure to check the product specs to see what kinds of pressure they’re able to handle, otherwise you might experience blowouts.
- Heat tolerance: You’ll want to check the temperatures a bag can handle as well. If you’re using a method of pressing that involves higher temperatures, you want bags that can be used with those higher temperatures. Again, using a higher temperature than a bag can handle may result in blowouts.
The Squish Strong’s rosin press bags are made with 100% nylon. They are double stitched, which is Squish Strong’s way of preventing blowouts. They are able to withstand temperatures of up to 300 F and “extreme pressure”, according to product specs. These bags are also compatible with any type of press you may have and the company doesn’t try to say that they “work better” with any one specific product.
- Double stitching. Each bag is stitched twice, making the bags stronger as a way to prevent blowouts.
- Durable enough for multiple pressings. Assuming the bags don’t blowout or rip in anyway, you can clean and reuse them for pressing more than once.
- Five of the bags I used from the 20-pack had a blowout. This resulted in quite a bit of oil being polluted with plant material. Packing less material didn’t seem to affect the chance of a blowout.
- Stitching soaks up oil. Even without blowouts, some of the oil was lost due to the stitching absorbing a higher amount of it compared to other bags.
- Not actually able to withstand “extreme pressure”. I have a 20-ton press and these bags definitely couldn’t handle that at full pressure. In fact, anything over 10 resulted in ripping or blowouts.
These bags are also available in 37 and 90 micron sizes. They are free of all chemicals and dyes, which makes them safe to use as filtration tools. Each bag can hold 15-25g of material and if you have less than that, it’s safe to cut and fold to size without worrying about it damaging the bags. The Squish Bag’s rosin press bags work best with pressures of 1,000-1,500psi and temperatures between 180° and 240° F.
- Holds a lot of material. You can pack in quite a bit of material into these bags without them ripping or tearing. I wouldn’t overdo it, but I had no problem with putting 15g into the bags.
- Safe to cut. The bags are easy to trim when using smaller amounts of material. They don’t tear when cutting and this doesn’t seem to result in a higher amount of blowouts.
- The 120 micron bags feel almost like sandpaper, definitely not as soft as some of the other bags used.
- 120 microns is probably a bit too high for me. The filtration is not great at all, resulting in a lot of plant material getting into my pressed oil. If I used these again, I would test them with one of the lower micron sizes.
- Lower temperature limit. These bags work best with temperatures under 240° F, which isn’t as high as some other bags. If you want to be able to use temperatures over that, these may not be the best bags for you
All rosin press bags from The Press Club come with a “no blowouts guarantee”, meaning the bags aren’t going to burst during pressing and ruin your oil by mixing the plant material right back into it. The bags are heat resistant (up to 375 F), capable of withstanding high amounts of pressure, and solvent resistant, so you can actually wash and reuse them. In addition to all that, the bags are made with 100% dye-free and food grade nylon, so you can trust that the bag itself isn’t going to contaminate your final product. The 37 micron variety isn’t the only one available, as there are a range of sizes 25-220 microns. The bags also come flipped inside out so you don’t have to do that yourself when you use them.
- Pre-flipped inside out. You have to turn all bags inside out in order to use them, so it’s great that these ones have already been flipped. It not only saves time, but you don’t have to worry about accidentally damaging the bags while flipping them yourself.
- Solvent-resistant. I had no problem with washing the bags with rubbing alcohol after using them. They didn’t fray or tear out all while being washed and were still just as durable as before.
- Since you can wash the bags, you can reuse them, in fact the product description says you can reuse up to five times. When I reused them a few times, I didn’t notice any increase in the amount of blowouts and they were still able to filter the material just as well as the first time.
- Highly durable. Not only can the bags handle high temperatures, they can also withstands high amounts of pressure. This makes them usable for a variety of purposes, since you don’t have to worry about them not being able to hold up to your preferred method of pressing.
- Lower yield. The lower micron units obviously don’t result in a high yield, which is to be expected.
- Not truly “blowout free”. I did have one blowout, which is still better than the other bags I’ve tried. It is worth noting that they aren’t 100% blowout free, so be mindful of how much product you are packing them with.
Rosin Press Filter Bag – Screens for Solventless Oil Extractions in Rosin Tech
Agar Industries is another company that flips their bags inside out for you. Their bags are made with food grade nylon and are dye free, making them safe to use for rosin extraction. They are washable and reusable and also contain a strong stitching design to help prevent blowouts. Agar Industries says to use these with their Agar Pre Press to achieve the best rosin pressing results.
- Inside out. Again, it’s a great time saver that these bags are already flipped inside out. I also don’t have to worry about damaging the bags while flipping them myself.
- Filters well. The end product that made it out of the bag was high quality, with very little plant material still inside.
- Absorbs oil. These bags hold in A LOT of the oil pressed. It sticks in the stitching, as well as the mesh itself, which isn’t great at all for yield. If you don’t fold the bags over, oil doesn’t get stuck in the folds, but then you increase the chance of having a blowout.
- I had a lot of them. The bags don’t seem able to handle high amounts of pressure or temperature. If it was just one or the other, that wouldn’t be too bad, but I personally don’t like to press at both low temperatures and with low pressure combined.
- Can’t hold a lot of material. Not the worst by itself, but using less material in the bags also results in oil being lost in the extra space inside the bag. The fact you can’t fill the bag entirely also means you have to use more bags to press the same amount of material that other products can do with one bag.
The clear winner is The Press Club’s bags. All have their own good points, but I feel The Press Club creates bags that have all the pros of the other bags wrapped up into one high quality rosin press bag. They can be used with flower, bubble hash, and sift. You can press at higher temperatures without worrying about the bags bursting open and they can also withstand high amounts of pressure, making them perfect for anyone, regardless of the temperatures or pressure you use. I was pleased with the quality of the rosin I receive from these bags. It had virtually no plant material left inside. The bags also didn’t absorb as much material as some of the other bags I tried, so even though the lower micron units tend to result in lower yields, the lower yield wasn’t because all my oil was being trapped inside the bag itself. Overall, I’d say these bags are great for anyone who is pressing rosin, whether you’re a first timer or an old pro, due to how many great qualities they have.