Want to build a Vacuum Kiln

I’ve been thinking lately about building a small vacuum kiln, probably only large enough to do maybe 20-50 board feet at a time.

I looked around and really couldn’t find any information on a unit this small.

What I am looking for is how much vacuum is needed?
What about heat transfer? If I use a water bed heater between the layers of wood will I be able to get enough heat transferred to the wood itself? (Remember, a vacuum is an insulator and does not allow heat to be transferred).

To begin with I won’t be looking for a perfect outcome since, as I understand it, there is a large learning curve involved in the process. Later, I may actually be able to make this work.

Thanks for any input!

-- Improvise.... Adapt...... Overcome!