the first run I did in a friends house on a friday night we let the butane evaporate naturally which took about 2 - 3 hours in total.
the second run with fresh trim again was in another friends on the following night and we instantly put the bowl in a bigger bowl of hot water to evaporate the butane quickly.
the butane seemed to be totally gone in about 30 mins but we kept replacing the hot water to keep the temperature and the oil soft so we could smoke it easier
but by doing this it seemed we totally purged the butane for sure and then after about 2 hours we finally let the water go cold and the oil.
afterward the oil when it finally got to cool down became very stiff and non-sticky ??
in fact was able to crumble some of it up like hash (and I mean easier than bubble hash if you are quick enough without letting your body heat start to soften it )
I guess this is similar to what you end up achieveing with the technique you mentioned ???
does this make sense ???
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