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- or - Rough and dirty vacuum testing: my path towards high vacuum |
➡ Basic vacuum setup:
starting from scratch, testing the pump, building a reservoir, measuring pumping speed. ➡ Building feedthroughs: once the reservoir is ready, it's time to build some feedthroughs for electrical wires and for gas feeding. ➡ First plasmas! Obtained from some kPa (around 8 Torr) down to around 250 Pa (2 Torr). ➡ Moving to a larger vessel: flanges, gaskets and a nice cart. ➡ Turbomolecular pump ... and its power supply. ➡ Plugging in a mass flow controller ➡ News: I just got below 1 Pascal! But barely. The gaskets definitely leak a bit, and this makes it harder to reduce the pressure further. Notes: employ thicker flanges! Thin flanges deform too much during welding, and this makes the pressure on the silicon gasket uneven, probably leading to the leakage. |