Hello,
I was reading Scarecrow's thread for a flavored packed column, and figured it wouldnt be hard to mod my VM still to be able to do the same thing. I sealed off the top, and added a U of 3/4 to use as a safety feature. Shown below.
EDIT: The U is filled with water to form a vapor lock
Now I have fully adjustable VM.
I can do full reflux with the VM valve closed and reflux valve open.
I can run as regular VM with the gate open
I can then make more vapor come out the VM valve by adjusting the cooling flow to the reflux condensor.
If any pressure builds up in the column, I will be notified by WATER coming out of the vapor lock before I start getting ethanol steam. In any case, I cant build up dangerous pressures in the column with this setup.
For rum or whiskey, I reflux for a while on a reduced packed column, then draw out the foreshots/heads at a slow trickle, then open the VM valve, and reduce reflux to a trickle.
As for results:
Ive done a rum run on 500mm (4 rolls) packing and came out with ~90% pretty flavorsome stuff.
Ive done a UJ on 375mm packing and it came out with an initial 85%, but steadily declined. However this was only a 8% 25L wash, so there wasnt much alcohol to hold the temps steady.