Reports until 14:33, Tuesday 06 May 2025
Vacuum Systems General (RbQ)
Daniel Grass - posted 14:33, Tuesday 06 May 2025 (12311)
RbQ Vacuum Chamber Vented and Pumped Down Again with 2D MOT Taken off and Plate Rotated

The pressure seemed stuck at 1.1E-6 Torr, so I vented, took off the 2D MOT, added a spare 2.75" CF blank flange from the Holometer (we have plenty of unopened 2.75" blank flanges) and tightened the screws to ~40 in-lbs. I took off the 12" x 6" plate that was attached to the 2D MOT. I noticed a small hair which I wiped away with an isopropanol wipe but otherwise the inspection looked good. I wiped the vacuum surfaces with an isopropanol wipe, rotated the plate 180°, and installed it, tightening the bolts to 70 in lbs. I turned on the scroll at 2:07 PM and turned on the turbo 6 minutes later when the pressure was 4.7E-2 Torr. The turbo reached full speed 70 seconds later with a power of 4-5 W a few seconds after that. 25 minutes later, the pressure is 8.7E-6 Torr, a bit worse than the past two times but we ultimately care about the final pressure. At 6 PM, the pressure is 2.2E-6 Torr.