I use a 110 to collect the kief, and a 195 to clean it up. The mesh size has everything to do with cleaning up the kief. My screens are aluminum and work fine. When first collecting the kief to separate tumbling for a very short time the kief falls through the 110, you could also use a 5 gallon or smaller bucket with a piece of loose screen stretch it over the top put in your trim bud whatever, just make sure it is really dry and gently shake it to collect the kief. if you card or put pressure on the trim you push unwanted particles through the screen. Try varying the amount of kief you put on the 195 before you gently rub it with the parchment paper...