Ok, it seems most people have cartos that they can refill by pulling the cap off.. I haven't got any of those yet.. so I'm using the "condom method" to refill mine. After I fill, I basically put the carto between my palms and do like a hand-warming movement rolling the carto up and down between my palms really fast trying to get centrifugal force to pull the juice from the center tube out to the padding/filter/stuff. Anyone else do this or am I just being weird by doing it? It seems to clear any juice out of the center pretty good and I don't vape on it till I can see down the middle.. This is on 510 cartos btw.