[Corey, Jim, Stephany]

BSC #1 Stage 0 Top Plate

This plate was placed on the granite table for pre-assembly work.  1/4"-20 & 3/8"-16 helicoils were installed on this plate.  Unfortunately, we did not have a tool to install the 5/8" helicoils.  Additionally, we also installed dowel pins.

HAM#3 Re-assembly

Last week one of the eyebolts installed on the Optics Table was found to be stuck in the table.  Today a 6' bar was used to attempt to turn it out and this 3/4"-10 Eye Bolt ended up breaking in the table.  There is probably ~1" Class B "threaded rod" now stuck in the Optics Table.  Initially thinking we would pull out this Table and swap it, ~130 of the bolts were pulled out of the table, but in this time, it was decided that we would probably keep this Table in place (so the ~130 bolts were re-installed).

The eye bolts we use for lifting plates have tons of thread (~2"), and each thread is an opportunity for galling a part in a plate.  In the future we should use nuts (as spacers) on these eye bolts, or cut these eye bolts down to a useful and safer length.

Since we decided to proceed with this Optics Table, we can now continue with assembling HAM#3 (install  Actuators, Sensors, Walls, weight for GS13's, release Springs, etc.).

Attached is the final positioning observations for BSC8.  Thanks to Scott David & Bubba.

The numbers in the top plan view show the measurements from the ends of the Support Tubes to the Chamber "D" nozzle.  Mirror numbers indicate a balanced location.  Accuracy is typically 1/32".  This system is in very good initial position.

The lower numbers are the vertical positions of the Support Tube.  We purposely leave these a several mils high to allow for sinking when the ISI is added.

To understand why the design elevation is 1060.5mm, see T1100194.

Contractors finished framing the building and began installing the exterior drywall. They will continue working on the exterior tomorrow.

Dust monitors show no catastrophic dust levels. Sustained counts of 3000-5000 at 0.5 microns near the H2 PSL. Attached trend shows 3 weeks of data.

Activities throughout the day
Kyle to Y-Mid to remove RGA isolation valve

 Craning over tube in LVEA

HEPI install work – removing iLIGO support stacks, install HEPI position support tubes

H2 PSL enclosure being constructed.

Commissioning of the HEPI Pump servo continues at LHO with the tweaking of PID control loop parameters.  Spectra of the voltage output from the Honeywell Pressure sensors are attached below.  The maximum allowed pump pressure fluctuations in PSI/sqrt(HZ) are calculated in the document T1100198.  The data was taken from the pressure sensor transducer outputs in-line with the servo box.  Data was then converted from Volts to PSI per the manufacturer's specifications (3000PSI/1V) .  A Dataq Instruments interface was used to record voltage input and record data in a text file using its software on a laptop separate from the single board computer in the servo box.  

The first plot is with no PID servo enabled; it is simply with the motor controller set at a speed that read out ~80 PSI.  The subsequent plots have PID parameters listed in title of the plot.  The maximum allowed PSI fluctuations curve calculated from the above-mentioned paper is plotted as well.  So far, the conservative PID gains have not brought the performance to the maximum allowed fluctuations.  The spectra does decrease in magnitude over all frequencies with increasing PID gains. Next, more aggressive PID gains will be implemented (several 10s to 100s) and data collected.  Also of note, new accumulators were installed Monday and pressurised to 75 PSI.  

Removed 10" to 4.5" skewed reducing nipple and the 2 1/2" angle isolation valve connected to it from the middle port of the SW corner of BSC6 and installed a 10"CFF blank in their place.  These items were the remaining fittings of BSC6's RGA (the RGA "tree" was removed a few weeks ago).  The RGA removal facilitates the relocation of BSC6.

Framing of the laser room is nearly complete. They have to finish half of the roof and then they can start installing the sheetrock.

There have been some concerns about dust levels, but a trend of the past three weeks shows that this weeks construction activity has not been abnormally dirty. I plotted dust monitors 9 (2k PSL), 7 (iLIGO HAM8 position), and 5 (beer garden).

Replaced NC solenoid valve on left tower of X-mid instrument air drying unit.  Building pressure maintained by use of portable compressor (4cfm oiless)

• Wood recylcing bin emptied
• H2adcumy had crashed, I powercycled and ran the startup script to get it going. Interestingly, the status box on the overview screen goes black instead of red when this computer goes down
• Diamond frieght pickup
• Clean room parts craned over beam tube to HAM12 area
• Ongoing construction for H2 PSL enclosure

One of the project controls team created a tribute to our assembly techs and the great work they have been doing.

Please note, this was done on her personal time.  Everything is edible except for the bolt and the tool.

Dave and Jonathan,

we repurposed the lhocds.ligo-wa.caltech.edu IP name from the old iligo system to the new aligo system. Users of the old servers will have to substitute "blue" for "lhocds" in their URLs to get to the old wiki, web pages.

We also ligo.org converted the new aligo CDS web/wiki server. Anyone with a ligo.org account can view the web pages and post wiki entries. In the future, when the wiki contains sensitive reboot instructions we may further restrict the number of subscribers.

King Soft water
Unifirst
Construction started on H2 PSL enclosure
Field trip
Praxair delivery to CP2 and CP5
Camera can removed from HAM4 squeezing table
Preparation for moving BSC6
Finished unloading clean room parts for end stations

Noticed that the instrument air at the X-mid was wet -> Investigation showed a switching failure between the drying towers.  I reset the electronics and observed a few cycles of tower switching.  Also observed that the regeneration flow valve was set for near 0 psi -> adjusted for ~50 psi. -> checked a few hours later and working normally.  Why was valve setting so far off nominal???

Construction began on the H2 PSL laser enclosure today. Contractors started laying the framing down, bolting the support structures to the floor.

Yesterday, BSC6 South door was pulled, after a couple rounds of chamber cleaning.
We installed the Support Tube 'Pillows' which fit under the Support Tubes in the chamber nozzles.  Once in place, the Scissors tables are used to lower the Support Tubes onto the pillows.  To lock them down, A cable goes around the Support Tube and shackles to a Bracket bolted to a chamber interior flange.  See photo, this is not tensioned up yet and there will be one on each corner.

Once the Exterior support structure is removed, further positioning constraint and bellows protection will be installed.

Hugh for
Terry & Christina; Jim, Randy, Scott & Bubba

Ran well pump today
Programed North crane so lights will stay on

The H2 PSL table was installed into its aLIGO position today. It was wrapped up in plastic to seal it from any dust, and we will add a protective layer of lacquered wood to cover the table during construction of the laser room.

H2PSL table was placed and epoxied in position.
Staging work was done at MY for the BSC6 move.

Betsy, Jeff and I did a measurement of the maximum obtainable pitch and yaw range on the rebuilt Quad #2 using an optical lever. According to Norna's write up, T1000268-v1 ( https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=11868 ) we should be able to get 1.4 mrad in each direction at the optic. At the DOF Test screen we applied successively offsets of +2556 and -2556 in pitch and +7863 and -7863 in yaw, which with the usual output matrix maxes out (32K) at least one of the OSEMs. The resulting deflections of the optical lever spot were +9.5 and -11.5 cm in vertical (+=down) and +5.5 and -6.5 cm in yaw (+=left). The optical lever baseline was 4.98 m. 

This implies a total range of 1 mrad in pitch and 0.5 mrad in yaw, which is rather less than expected. A big chunk of this is that the actual UK driver boxes for the test stand were not built to the 200 mA max output assumed in T1000268. To check this, the voltage across the face1 coil was measured at the simulated vacuum flange, with 32K-1 of offset applied at the Output Filters screen. The resistance (including that of the cables) was 39.9 ohms and the voltage was 3.69 V implying a maximum current of 92.5 mA.

The fact that the pitch range is larger than the yaw is probably connected with the fact that the fundamental pitch mode frequency is rather lower than in the model, i.e., there is more pitch compliance than expected.