Yes that oily residue is primo, I stuff nuggies through the tube to clean mine. I reccommend you do the same. You can also leave a nug in the tube while you vap. Then place it in your vap and go for it. If you have a vapir you don't need to break up the nug just place it in the bowl and have at it. Then save the post vape when you fill a mason jar make brownies.