Hey thanks for the help! Yeah the customer really wanted to do a vacuum because he uses a fair amount of oak and the dry time for oak is sped up when using a vacuum vs kiln. I'm just going off what he has told me. But he was open to the idea of a regular kiln sounds like that's his best option.
A client asked me to look into designing a vacuum chamber for drying out lumber. I am a decent fabricator but sadly not so great at the physics side of things. I know the chamber I'm building will need pretty thick material and a lot of reinforcement. He wants it to be roughly 10'x3'x3' inside...