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Beginning warm metrology measurement of RTM-012 while pumping down. CryoPlate temperature gives something like 31C - typical of the condition when
pumpdown is performed (to reduce as much H2O as possible. RSA is obviously somewhere between 20 and 30C. After aligning the first time,
I was shocked - SHOCKED(!) to witness that TS7-1 on TS5 optical table shifted by 1-2mm (occurred when Yousuke and I were attaching the back flange
for pumpdown following aliveness test). Noticed that one of the kinematic tooling balls was touching only 1 of 2 tooling cylinders on the E side of
the room. I cut one of 3 cable ties used for seismic fixturing but that didn't fix the problem. Apparently the friction against the ball on the flat
(W side of room) was sufficient to keep the E side above its landed position. Should have checked for proper landing before aligning. Reperformed
alignment, which required a ~2mm axial correction with the displacement sensor and ~1mm lateral (vertical) correction to recover alignment. I guess
I didn't realize that gravity might not be sufficient to bring TS7-1 back into a repeatable position with the existing kinematic components. measurement should be complete by the morning sometime (8am or so?)
May 2, 2018 (5/2/2018)
