WH- I actually just tried making the butane extract like a week and a half ago...
What I did was use a pen(like a reg plastic writing pen) rather than a pvc pipe as I saw most in the methods i found researching this process via the web. I took all of the guts out of the pen, stuffed a metal screen in the writing tip and re-inserted it. Then from the back end of the pen I took great bud, and some hash for good measure, and packed it very very tightly. i used the ink tube from inside the pen to pack it after every couple pinches i put in so it was very tight. Then i burnt a hole in the 'cap' to push butane through and put it back on pen. I used like a third of a gram of hash and prob a lil less or equal of green and got a nice small amount of H-oil. After i shot the butane though into a bowl till it turned from gold to clear i put that bowl into another bowl, kinda like a double boiler w/ pans, just warm tap water brings the butane to boiling point. after ten min or so it was just a residue(hash oil). i used a knife tip to scrape it up and a lighter to make it drip onto bowls of bud. I Also smoked it straight off of tin foil and it kinda made me feel like a heroin head until the buzz kicked in. It was great, but i'm a sort of a light weight these days. There's my experience. wow that was long. I almost forgot when I tried it right after making it, it tasted bad of butane and really hurt my lungs but the next day it was better and it stopped tasting bad completely after like three days so maybe i didn't 'Double Boil' long enough. but after the taste went away and i stopped minding smoking off foil it was a great high.

H3RB!!