Hi guys So i would love to try and make some more BHO from my less attractive bud. I tried doing a little run this way: 1/2 l. coke bottle. Drilled 3 holes in the lid and 1 in the bottom. Put a piece of cotton into the lid as a filter but seems like gas went right through giving too little result. So do i need to vacuum the BHO in order to make it free from butane? The little amber thing i got smelled fantastic - could even smell Jack Herer still.