Water Extraction
Resin glands can be removed from the cannabis plant by agitating the trim in cold water, typically ice cold water or water that has been chilled in a fridge overnight. The trim is placed in a bucket and the cold water is poured in on top. The whole lot is swirled or mixed around using a blender. After mixing you let it sit for a few minutes before scooping out the skuff that is floating on the surface. The remaining liquid is strained through a sieve. By sieving this liquid through a coffee sieve you will be able to collect most of the trichomes, as they will not pass through with the water. Just let the coffee sieve dry and hey presto!, you got excellent grade skuff to make hash from.
The basic idea behind this is that cold water breaks the glands away from the leaf matter. The glands will eventually sink to the bottom of the bucket because they are heavier than water. The bulk leaf matter should stay afloat which can be easily scooped away.