Hi All, I think this project is a really interesting one, and not completely hopeless to do under a budget. Here are my thoughts, for what they're worth. (And I apologize in advance if anything has already been said). -Regarding pumping to <1E10-4 Torr: You should be able to do this with a two-stage rotary vane pump (~2E-3 Torr) plus a diffusion pump -- each which are relatively inexpensivby PS - MetalicaRap