Re: re vac forming

Rough pumping can be done with a vacuum, and if you want to achieve
higher levels of vacuum, you can make a vacuum pump out of an automotive
air conditioning pump.
If you have a gage and can tell how much vacuum the shop vac can pull,
you can run both at the same time and valve off the shop vac once you
hit it's limit. If you don't, the other pump will be working against it.

Jon