Updated September 30, 2019
Introduction to THCA:
There are many methods (times and pressures and techniques) to mechanically separating THCA from rosin. Most work well. Some do not. This is the one I use, as I have had consistent success with it.
CannaPlates THCA guide is only a guide. Your results may vary, as mine have, in this not so cheap adventure. Hopefully I have borne most of the cost of this adventure, so that you don't have to make the same mistakes. Thca is made by separating the components of the rosin. The mild heat and mild pressure of this process, causes the thca to separate from the rosin and solidify into a chalk like form, that snaps like drywall.
To begin with you need the right kind of rosin. Rosin that is clear or shatter like or runny will not work. Do not try to use these kinds of rosin and expect results. You will not get them. The rosin MUST be cakey. It must be chunky like ..well ... chunky peanut butter that has dried out.
The more crumbly you can get your rosin the better off you will be.
The return rate on this process is quite low, while the process I use gives a better than average return, so it can get expensive, but the payoff is melting your face off good. I have found on average, that you will get 1/3 of your weight back in THCA using this method, if done reasonably well.