Whats this CFM number for vacuum pumps?
This is the cubic feet per minute of air that the vacuum pump would move if the input and output of the pump were unrestricted. Apparently, this is the best they can do in terms of specifying how fast the pump can bring down an arbitrary volume. Probably there’s some easy way of figuring what pump is right for what volume, but I never found it. Best I can suggest is going rummaging on the web. In my case, I lucked out. I found a new salesman at a local company that reconditions pumps that was willing to take the time to help out a guy who probably wouldn’t be a repeat customer. If you’re in the San Francisco Bay area, you owe it to yourself to check out Duniway Stockroom Corporation. The guy who helped me out was named Kevin. I have no idea if he will be happy to see repeat business, but it’s worth a shot. They sold me a pump on a sort of a rental deal: I got to try it out for a few days, and if I didn’t like it, I could bring it back for a 90% refund. They hadn’t fully reconditioned i
