How to Mechanically Separate THCa from hash rosin

Hash rosin is a versatile input and can be used to make a variety of solventless offerings through further refinement. Refining your rosin into THCa can be a easy and fun way to create a more potent concentrate that will remain stable at room temperature far longer than conventional hash rosin.

THCa is Tetrahydrocannabinolic acid, which is a precursor to THC. When THCa is decarboxylated it is converted to THC. To perform this extraction you need input material that is fresh and has not had a chance to decarboxylate (either through heat, time or a combination of the two). Fresh frozen material is best but dry cured hash will work as well, as long as it is not too old.

materials and methods mechanical thca separation

Items Needed:

  • Hash Rosin
  • Nylon Rosin Bags (25u, 120u)
  • Parchment Paper
  • Scissors
  • Rosin Press

Prior to attempting THCa mechanical separation you must ensure that the hash rosin input material is buttered up (example of this consistency can be seen below). If you attempt to mechanically separate THCa with fresh press hash rosin, the rosin will simply flow through the nylon bags leaving you with a little bit less of the same input you started with. The buttering process is a form of recrystallization which allows the THCa to be mechanically separated from the terpenes and other compounds in the hash rosin.

nucleated hash rosin example

Once you have your buttered up hash rosin ready, the THCa separation process can be started by molding the material into a cylindrical shape and placing the material in the freezer for about 5 minutes to prevent it from sticking to the inside of the 25 micron bag.

hash rosin prep for thca mechanical separation

After removing the material from the freezer, proceed by inserting it into the first rosin bag(25u). This must be done quickly to prevent the rosin from sticking to the inside of the bag, if you find that the rosin is too sticky place it back in the freezer and try again after 10 minutes.

bagged hash rosin for thca mechanical separation
hash rosin prepped for mechanical thca extraction hashtek

After successfully getting the rosin into the first bag, proceed by molding the rosin into the a uniformly spaced rectangle.

THCA separation prep molded hash rosin

At this point you can proceed by trimming the excess from the 25u bag, folding over the end and inserting the folded end first into the 120u bag while ensuring the seam of the 25u bag is opposing the seam of the 120u bag.

Double bagged hash rosin ready for thca extraction

Now that your material is bagged up and ready to go, we can transition to the extraction portion of this process.

Mechanical separation essentially forces terpenes to dissociate from bulk hash rosin material by a combination of pressure and progressive heat. Typically we will start our extraction at around 105F, and increase temp on each successive press by 10F until the amount of terpene sauce output becomes negligible.

Caution must be taken to start with low temperatures, if high temperatures were used from the start (~180°F) the material may not separate and would flow through the bag. THCa would dissolve into the terpenes because of the higher terpene concentration and higher temperatures, both of which increase THCa solubility. There is also decarboxylation that can occur at higher temperatures. Remember that THC does not recrystallize and cannot be mechanically separated. When starting with low temperature the terpenes can be extracted slowly without dissolving the THCa. When higher temperatures are achieved gradually there are not enough terpenes to dissolve the THCa, because they will slowly be extracted out with each temperature increase. It is very important to work in batches and not try and rush this process.

Once your material is bagged up and ready to go, preheat your rosin press plates to 105F. When target temperature has been reached, place bagged hash rosin into a pre-folded piece of parchment paper and sandwich it between the rosin plates so its snug and doesn’t slide when pulling on the paper.

THCAtek pressing out terpene sauce
Terp sauce bleeding through rosin bag first cycle

Wait until you begin to see some terp sauce separating prior to applying more pressure. Failing to do so can cause blowouts.

thcatek terp sauce drip shot
thca tek terp sauce drip shot two

Once you see that there is no additional terp sauce separating you can remove the puck from the press, and proceed by removing the 120u, and 25u bag, which will require scissors and a pair of glove as this part can get quite sticky.

thcatek first cycle separation hash rosin solventless

The sticky substance that is being separated is often referred to as “terp sauce” and can be used in the creation of other hash rosin derived products.

thca tek first cycle bag change solventless hash rosin
thca tek first cycle bag change solventless thca extraction
thca tek first cycle output material solventless thca extraction

As you can see above, the material output from the first stage of separation can be seen as still having a little bit of terpenes, to remove these we will place this material into a set of new 25u & 120u bags and repeat the process at the next temp (115F, 125F, 135F, etc). The number of temperature steps taken depends on personal preference of output, the further you go the cleaner the output. However, each extraction step taken will contribute to a further loss in output weight, so its a balancing act at the end of the day.

second cycle thca extraction solventless

THCA tek second cycle output solventless thca extraction

This is the material after the 115F press, which in my personal preference is sufficiently separated. However, if using cured hash rosin input, you will most likely need to repeat this process at higher temperature to attain similar output, this is due to higher sesquiterpene relative abundance in cured hash rosin as opposed to live rosin.

thca tek final output solventless thca extraction method

That is all there is to it. Contact us if you have any difficulty with this process and need help optimizing extraction parameters for your application.

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