Kinda like how I make ISO hash. I think my way is much safer though.
You'll need:
container that will seal, (old pasta sauce jar, mason jar etc.)
Pyrex baking dish
fine strainer (get the finest mesh you can find)
rubbing alcohol (get the highest percentage you can get)
Razor blade
Pot of hot water and a stove
1. take trim and put in freezer for at least an hour (the crystals come off quicker frozen)
2. prepare a pot of water on the stove bring to a boil
3. Take the trim and put in a mason jar or anything that seals well, put in enough alcohol to cover the trim
4. Shake for 40-50 secs
5. strain into the pyrex pan and place on top of pot of boiling water. I like to do small amounts at a time it goes quicker than filling the pyrex pan up all at once.
6. as the heat gets higher in the pyrex the alcohol will evaporate and the hash will start to harden
7. after the alcohol is ALL evaporated and the hash starts to get hard its time to scrape w/ the razor blade
After a run or two you'll get the hang of it, just make sure you evaporate ALL of the alcohol.I also will do a double wash. After you strain the first time use that alcohol to do some more trim, you wanna get as much crystals as possible into the smallest amount of alcohol. Like I said after my first run I got the "feel" for it and it works like a charm now.
Good luck