This was a project work I was involved in during a part-time job at university. The goal was to set up a working UHV (Ultra-High Vacuum) chamber for the purposes of teaching how to operate such a device and for testing small scale PPT (Pulsed Plasma Thruster) electric propulsion RCS engines.
The design was a two stage pump system with a Roots-pump as the first stage and a turbo-molecular pump as the second.
Both pumps and the chamber were repurposed second hand / thrown away items, so it wasn’t clear at all if the assembly could be made to function properly. However, despite these concerns, it met, even exceeded requirements in the end after some tinkering on various parts. We were able to reach pressures as low as 1e-7 mBar. I’m rather proud of the success of this project given the limited budget that was available.