Scraps of text for incorporation in the VIS Meeting Minutes
Type B (Mark)
Past week report
At Kamioka (Mark, Fabian, Enzo, Perry, Hirata-san):
- We counted the used/broken/unused/need cables for Type B.
- Hirata-san and Mark installed blades in three LBB blade units.
- Hirata-san checked the LBB blade units to see how badly the blade tips were misaligned. The bases will need to be moved towards the clamp end by 21 mm. It is probably not feasible to turn the screw holes into slots, so an adapter part will need to be designed.
- We checked that the new in-vacuum geophone cables that Takahashi-san had got for us were the proper new-style ones. (Thus we will need in-air descrambler cables.)
- Shoda-san sent Enzo a document by Joris on the tuning of the LVDTs, so he stated working through it. He also researched the specifications of all the coils (PI and SF as well as BF.)
- We found the damper magnets and the template for placing the magnets on the ring for the SF.
- Hirata-san installed and wired up the PI yaw stepper. The vertical stepper still needs wiring, and the horizontal stepper wiring needs to be made vacuum-compatible.
- We installed safety bars on the ±X side of the assembly frame about 3 m off the floor, so they are at waist height for a person standing on one of the tall ladders. The one on the +X side will be very good for safety where it is, but the one on the -X side will need re-doing: it is too close and not very securely attached because of interference from vacuum pump cabling.
- We unlocked the inverted pendulum and experimented with adding weight. It was still stable with 4 layers of arc weights.
- We also experimented with getting both the IP centered and the security structure vertical (so that the suspension hang centrally within it). We managed to get it all right with a combination of leveling the PI with the jacks and moving the IP with the fishing rods.
- Adjusting the verticality of the SS had left the bottom of it off-center in the assembly frame, so we picked the entire system up with the crane and moved it in +Y and -X a few mm to re-center it.
- We started to remove the PI so we could do various adjustments (check the SF LVDT, reconfigure the Cu damper, add the hex cable clamp on the rod and hang the magnet disk for the SF damper) but gave up when the PI-SF jammed in the SF.
Plan for coming weeks
For more detail, see KAGRA/Subgroups/VIS/TypeB/ToDo.
Week of 5/15:
- Enzo from Tuesday 5/16 (driving test), rest of team from Monday.
- Fix PI-SF rod jamming.
- Remove PI and SF cap.
- Continue debugging SF LVDT.
- Reconfigure Cu damper ring on SF.
- Add magnets to upper SF damper ring.
- Add cable clamps on the PI (a few places are inaccessible when the PI is on the assembly frame).
- Reinstall PI, this time with rods and damper ring.
- Reinstall PI-SF rod, this time with hex cable clamp.
- Prepare for PR2 bellows removal on 5/15 (move table with tools).
- Cable/test PI horizontal LVDTs and steppers.
- Install/cable/test geophones.