Although I've seen 1/2" used, I'd go for 3/4" and here's why: The
diameter of the pipe determines how much heat energy you can apply to
the still without generating some internal pressures in your still.
Because I strive for very low internal pressures, and because I've had
an early wood-fired still with a 1/2" outlet that kept blowing my
overpressure valve (admittedly at fairly low pressures), I'd stay away
from 1/2" at reasonable energy inputs.
On the other hand, if you're looking at using a thumper, you're going to
have to deal with elevated boiler pressures anyway.
I do a little stovetop still that has a nominal 3/8" vapor path, and it
works great at 100-150W power input. Much higher heat would be a
Zymurgy Bob, a simple potstiller
--- In Distillers@yahoogroups.com, "Rick W" <rw71457@...> wrote:
> I was wondering if I could use 3/4 copper pipe for the column on a 3
gallon pot still or if that would be too small. I would reduce it to 1/2
and add a small thumper to finish up.