Wrong. Depending on quality of the herb(trimmings or actually whole buds and of course potency) and how many cans you use (you can usually do each ounce twice(as in repeat the process twice on the same oz)) and also the size of cans you use. You ALSO WANT TO USE CALIBIRI BUTANE OR SOMETHING SIMILAR! Cheap ass butane from your local gas station IS NOT GOOD TO USE as it contains a TON of chemical additives like smells etc..and can make you oil very gross and almost unbarable to smoke. Stay away from anything that isn't at least 5x purified. Bernzomatic etc is bad news and a complete waste. EDIT: I am going to start a proper oil thread with pictures. I think I am gonna head to my local hardware store tomorrow and see what I can put together on the cheap. With using proper materials of course. Just a "build your own oil extraction setup on the cheap" type of deal with real detailed pictures and actually readable writing with punctuation etc. cause you're info was good just not as accurate or informative as you could've made it. Copper is bad to use. So is all plastic. Stainless steal or glass tubes....but even glass tubes are harder to clean because it's more porous material then stainless steel. Doing more then an ounce or 2 at a time is a waste also because you can't get the butane to cover such a large area efficiently. The smaller the batches the better chances at getting higher grade oil. EDITING EVERYTHING!: WHY THE FUCK DO YOU FUCKS KEEP BUMPING OLD THREADS! ARRRGGGHHH!!!