Along these lines, and another way to try, yesterday I used a capsule -- empty, with a lid on it -- atop a micro dose (at least that's what I'd call it, I have no idea of the weight of it). I was concerned about creating pressure against the c/u and consequently the housing, so I did use a very small amount, then plopped the empty capsule in. When finished (like 2 or 3 pulls at 190C) it was well spent and flattened out to about 1/16" inch thick. I had to poke it once to crumble it so it would fall out.