Misturemike said:yes...make sure you only spray the glass portion of the apparatus outside. I suggest setting it in a tub or any vessle that can handle the glass pans size, and fill it with hot water. having the glass already warm/hot to the touch will allow you to evaporate the butane at a much faster rate, usualy a 5.5 ounce can worth in about 5 mins. once no more liquid is present, take the glass pan and set it up on your electric heater and let sit for 2-3 hours on low(145-165F). scrape and enjoy. my rule of thumb to know the oil is all the way purged is if you put a a small amount of oil on a paper clip it should not sparkle or spatter. it should just melt with few or no bubbling. i've been making BHO for 7yrs now, and i see lots of tainted oil. i will post the results of some oil we had tested 5 years ago, astounding results....