OK try this method.

Switch volcano heating element ON - do not turn it off - keep it on all the time.

Measure some bud. I usually use 0.3g but this might be a bit much for some people.

Don't grind it (no I'm not kidding)

Set volcano temp dial to 4.5/5.0

Very roughly break the weed into chunks and into the volcano - 5 or 6 lumps

Run the volcano - inhale bag full

Increase temp by 0.5 - run again

run again unless no more vapour appears....

remove weed - break it up some more

run again

up the temp to 6 and run again

take the weed out - grind it - back in again

Up the temp to 7 (205 degrees 'C')

Keep going (all the way to Temp 9 if you want) until no more vape happens.

I find this extracts a fuck of a lot of THC and keeps the taste amazing all the time, each time you break it up even more flavour comes out - at high temps it doesn't taste so good. Afterwards though this vapor-poo/duff is not much use and isn't good for smoking or brownies.

Don't beleive that the Volcano only extract 40% THC - it extract 40% in ONE RUN continually grinding and exposing the plant material means you really do get a lot more THC out of the weed compared with setting it on fire.