Does anyone here have any experience with UHV systems. I'm starting a project that will require some UHV but haven't ever really messed with it. Long story short I was able to scavenge an ion pump and oil diffusion pump from my university, while trying to find documentation on both pumps I was told by a representative at JEOL that my diffusion pump should produce the same amount of vacuum as the ion pump. However, everywhere else that I've looked online tells me that the diffusion pump should produce a great vacuum but it won't get close to the ion pump. I'm kind of torn and honestly if I can help it I don't want to mess with the ion pump until later especially considering I can't find documentation on the electronics and don't have any of the control hardware. The diffusion pump should be waaaaaay easier to deal with and if I can produce the same amount of vacuum as the ion I don't mind waiting around for it to produce peak vacuum and really don't give a shit if it burbles oil back into the chamber I'm using.
Something to note is that the diffusion pump does have a stainless steel seal as an interface.