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==== Past week report ====
At Kamioka (Mark, Fabian, Enzo, Hirata-san):
==== Report for week of 12/25 ====
 * Hirata-san got the L-brackets machined and washed, and installed them on the IM ring bars.
 * Shoda-san recovered the BS from the power outage on 12/25.
 * Miyakawa-san fixed an issue with the SR2 RTM which had prevented it from running.
 * Shoda-san, Hirata-san and Kozu-kun weighed the IM without ballast masses, and then added the lower masses and installed the IM on the assembly frame.
 * They cleaned the assembly frame and installed new jack receptacles on the load gauge adapter.
 * They installed the winch system on the IM, and inspected the clamp pieces for possible scratches.
 * They ran cables for the SR2 steppers and OSEMs.
 * They calibrated the BF LVDT.
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 * Inspected LLB in tank - in a good position, but not very clean - apparent water spots and dirt.
 * Found the geophone adapter plates.
 * Retested SF FR stepper - still good.
 * Finally got SF LVDT working:
  * Found a short in the primary coil due to Al foil used for mechanical reinforcement at vacuum feedthrough connection.
  * Did a full calibration and found that linear range was too small (0.75 mm!) and did not cover nominal keystone height.
  * Decreased gain to increase linear range.
  * Adjusted the height of the yoke and secondary coil unit to center the linear region around the nominal keystone height.
  * Implemented velocity damping.
 * Found all parts for the LBB and damper rings.
  * Cu segments and some other parts were very dirty - wiped carefully for now, but should be properly cleaned before final install.
  * Outrigger parts for LBB have M16 thread cut directly into Al but should have had M16 helicoils. This is a galling risk with Ag-coated rod receptacles. Hirata-san organized rework.
  * Some special lock nuts are in short supply and are being borrowed from supply at ATC for next batch of BFs.
 * Made remaining two geophone in-air descrambler cables (total three).
 * Installed a thermometer supplied by Kokeyama-san on the tower around the BS tank.
 * Prepared the SF damper.
  * Designed a pattern of magnets for the two-segment arrangement of SF damper and laid it out on the magnet ring with the template.
  * Moved the Cu segments on SF cap by 30° (the cap had not been in the right position earlier).
 * Reinstalled PI:
  * Raised the PI with the crane and hooked the SF damper ring. Some of the rods did not fit the receptacles due to tolerance issue, but by going through a large number of rods and receptacles, we found three working sets.
  * Craned the PI onto the frame and suspended the SF/... section, this time with the hex cable clamp on the F0-SF rod.
  * Tensioned the PI yaw return spring, installed (but did not cable) the yaw stepper and adjusted the yaw of the SF/... section. We worry the return spring is not stiff enough.
  * Installed (but did not cable) the geophones.
  * Recentered the IP. The extra weight from the geophones (≈42 kg) and SF damper ring (≈17 kg) had brought the IP to near the point of instability, so we removed one arc weight (≈17 kg) and rearranged the other two in the top row to be symmetrical.
  * Added ballast to set the height of the F0 keystone. We now have about 6 kg in hand (due to removing one of the Cu segments for the SF damper). This should be enough margin for cables, temperature fluctuations etc.
==== Report for week of 1/4 ====
 * Mark fixed a number of errors with the Type B screens.
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==== Plan for coming weeks ====
For more detail, see [[KAGRA/Subgroups/VIS/TypeB/ToDo]].
==== Report for week of 1/9 ====
 * We weighed the mirror in its box (and later the empty box), and the RM.
 * Fabian worked on the SR2/SR3/SRM mass budget and did an inventory of spare ballast masses.
 * We hung the SR2 and RM.
 * We assembled the bottom section of the security structure below the RM.
 * Hirata-san gave up on waiting for a third quote for the blades and blade parts and started the ordering process.
 * Hirata-san got rod cable clamp parts from Takahashi-san and worked on drawings for the improved BS vertical and yaw adjusters.
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Weeks of 5/22, 5/29:
 * Retest SF stepper every day, to see if problems recur.
 * Find/install geophone adapter plates or improvise replacement.
 * Reinstall PI, this time with rods and damper ring.
 * Reinstall PI-SF rod, this time with hex cable clamp.
 * Cable/test PI geophones LVDTs and steppers.
 * Reinstall LBB blade units.
==== Plan for week of 1/15 ====
 * Shoda-san at Mitaka making OSEMs.
 *
==== Plan for week of 1/22 ====
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    ==== Plan for week of 1/22 ====
 * Mark, Fabian, Enzo, Shoda-san at Kamioka Tue-Fri.
 * Hang SR and RM.

==== Vacation Info ====
 * Enzo 1/30-2/19 (at Mitaka 1/29, part of 1/30)
 * Kozu-kun 1/29-2/2

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for week of 12/25

  • Hirata-san got the L-brackets machined and washed, and installed them on the IM ring bars.
  • Shoda-san recovered the BS from the power outage on 12/25.
  • Miyakawa-san fixed an issue with the SR2 RTM which had prevented it from running.
  • Shoda-san, Hirata-san and Kozu-kun weighed the IM without ballast masses, and then added the lower masses and installed the IM on the assembly frame.
  • They cleaned the assembly frame and installed new jack receptacles on the load gauge adapter.
  • They installed the winch system on the IM, and inspected the clamp pieces for possible scratches.
  • They ran cables for the SR2 steppers and OSEMs.
  • They calibrated the BF LVDT.

Report for week of 1/4

  • Mark fixed a number of errors with the Type B screens.

Report for week of 1/9

  • We weighed the mirror in its box (and later the empty box), and the RM.
  • Fabian worked on the SR2/SR3/SRM mass budget and did an inventory of spare ballast masses.
  • We hung the SR2 and RM.
  • We assembled the bottom section of the security structure below the RM.
  • Hirata-san gave up on waiting for a third quote for the blades and blade parts and started the ordering process.
  • Hirata-san got rod cable clamp parts from Takahashi-san and worked on drawings for the improved BS vertical and yaw adjusters.

Plan for week of 1/15

  • Shoda-san at Mitaka making OSEMs.

Plan for week of 1/22

Plan for week of 1/22

  • Mark, Fabian, Enzo, Shoda-san at Kamioka Tue-Fri.
  • Hang SR and RM.

Vacation Info

  • Enzo 1/30-2/19 (at Mitaka 1/29, part of 1/30)
  • Kozu-kun 1/29-2/2

KAGRA/Subgroups/VIS/TypeB/Minutes (last edited 2022-10-28 10:02:46 by fabian.arellano)