^ A friend recently made the mistake of an overnight soak and resulted in a black goo that was very harsh to smoke, although still quite potent. He informed me that a more experienced friend had infact confirmed that 30-60 seconds is all you want to soak the shit in iso for because past that just extracts chlorophyll which affects potency and enjoyability (as well as presumably health) to smoke.
I save stems for about 8-12 months and performs a butance BHO extraction on them (technically only done once), I got a pretty shitty yield but there were many factors I overlooked in undertaking the process in the most efficient way. For example I didn't grind my stems, I used less butane than I would of liked (it wasn't a full can and I lost some to the atmosphere before I got a good seal happening on the vessel my green was in) and then stupidly evapporated it on a plastic container (stoned, drunk and sharded stupidity hey... 8)) so I really got a small amount. Not sure how much more I would of got if I had my shit down pat better because I can't imagine a monster yield from a couple ounces of stems.
I have always understood BHO to be superior to iso hash, and honestly when sampling a friends iso hash only a fortnight before making my own BHO I found the iso hash to be 2/3 the potency at best of my BHO/honey oil.
My stem collection is getting back up there, probably only 60-70% of what it was when I did my last extraction but I figure if I took better care to not make some past mistakes I could possibly get a better yield? The only concern is I don't want to do it too early and get fuck all.
Definately keen on opinions between the difference between iso and butane hash, in terms of potency, yield, harshness when smoking and difference in the high (if any). I had my heart set on another run of BHO but if I get some responses saying iso is better I might go that route. The final question I would have is does iso evaporate at a rate similar to butane, if not would you say its quicker or longer to evaporate the iso? I do live at home and have limited oppurtunity for these types of experiments so time is definately a factor for me too. I found 70% or so of the butane evapporated really quickly but the last but just took ages and honestly even when I smoked it I reckon there was still a little in there... My method for evaporating was filling a lerger container with boiling water and then placing my smaller vessel with the BHO/butance mix inside that, so as to avoid any open flame and potential fire hazards.