eLIGO HAM6 ISI Removal

(Bubba, Chris, Corey, Hugh, Mark, Randy, Zach, with Jodi & Dale documenting)

::::  Timeline  ::::

• May '08:  eLIGO HAM6 ISI Installed.
• Jan '12 (this week):  eLIGO HAM6 ISI Removed (Because HAMs need to be moved and cleaned)

::::  The Work  ::::

This week the eLIGO HAM6 ISI was slated for removal (this is due to the Chamber needing to be moved and eventually cleaned). 

On Wednesday, Hugh and the Apollo crew started staging for the work (primarily by positioning the Installation A-Frames & getting other equipment ready to go).  I went into the chamber to install our Trolley & Hoist Connector Blocks and to disconnect all cables from feedthroughs.  With regards to cabling, some of these cables were really tough to pull from the feedthroughs; the OMC cables were especially tough, and I had to yank on the actual cable (vs. the connector) and as I did this the band came undone, and the shielding came became frayed (this cable is obviously damaged).

Yesterday (Thurs), the primary work of fully assembling the Installation Fixture around/inside HAM6 occurred, the HAM ISI was removed, and Installation Fixturing was removed.  With Hugh's preparation of parts and the Apollo crew's expertise, this job went super smoothly.  Tasks started roughly around 8am: 

• Swapping Cleanroom sock (not sure what this did for us.  I think we'd want to have a sock similar to the sock being used at BSC8 (and used for the 5/2008 ISI installation.  The sock which was swapped didn't give us anything for movement of the crane [meaning we had to move the cleanroom up against the Tube & leave it open quite a bit to use the crane within the cleanroom])
• Putting a layer of Viton/ameristat padding on the ISI Cart
• Removing chamber's top Conflat
• Needle-ing both I-Beams through chamber

At this point it was around 11:30am, and I decided we break for lunch (vs. leave the load suspended on the Installation Fixture Trolleys).  After lunch we picked back up:

• ISI lifted off Support Tubes and transferred to Trolleys
• Staged HAM Cover on Optics table for when we can drape it down when we disconnect from Trolleys
• Move cleanroom as far north as humanly possible (we covered up the back side of the HAM Chamber with a few C3 Covers)
• Pulled the ISI out via trolleys (only required a little force from Mark & I)
• Transferred back to crane, disconnected from trolleys, pulled down ISI-cover
• Laid down ISI on Cart
• Moved cleanroom as far South as we could (ISI outside cleanroom, crane moved outside of cleanroom & close against northface of cleanroom for next pick of ISI), and also removed the Front A-Frame (to get it out of the way for moving the ISI to the Storage Container)
• ISI was picked up off the cart via crane from outside (the Cart was never rolled), and lowered onto the Storage Container base
• Storage Container had all threaded studs already in place & ready to go
• The Hoist & Trolley Connector Blocks were removed from ISI & the lid was attached to the container.
• The remainder of afternoon was clean-up:  removed I-Beams, rolled A-frames away, re-installed Top Conflat on chamber, etc.

On Friday, some final loose ends were completed--Mark went in-chamber to remove some conflats (for removal of the Septum plate); he also removed "Riser" hardware for the ISI (these were parts which were sandwiched between the Support Tubes and ISI Stage-0; I believe they were primarily for shimming up the ISI for eLIGO; not sure whether we still want this hardware, but Mark is bagging & tagging it).

Lots of photos of this activity is now in ResourceSpace here.

Rest in peace!

plots of dust counts

Attached are plots of dust counts > .5 microns. I have included a plot of the mode of one of the dust monitors to show when they were off-line due to the time it took to recover from the power outage.

H1 PSL installation

Standoffs for the floating layer of sheetrock were installed. Several of the lower floating panels of sheetrock were attached as well. Electrical work inside the walls is getting close to being finished.

Gerardo, Kyle - Restarted turbo pumping at Y-end following site power failure

Test Stands in Staging Building restarted

The suspension and seismic test stands have been started after the power failure of this morning.

LHO site power outage

We had a site power outage over this period:

Jan 26 08:35:48

Jan 26 08:36:08

approx 20 seconds in length. CDS systems have been recovered. We took the opportunity to swap out the old style timing master in the MSR.

plots of dust counts

Attached are plots of dust counts > .5 microns.

A visit to the TMS-Y

Keita, JohnM, DanH

We did some work on the ETMY transmon suspension: clamping cables on the back face, and installing (but not tightening) the cross-braces on the front and back.  Pictures attached.

Before and after the clamps were applied we noted the values for the OSEMs.  Things changed after the clamping, but not too badly; JohnM has the numbers if you're curious.

One of the electropolished nuts for the cross-braces was malformed in a strange way, so the back brace is currently held up by seven bolts instead of eight.

We noticed there were assemblies of what looked like BOSEM magnets on the suspension's first stage...perhaps for eddy dampers that haven't been installed?

We also wanted to assemble some mirror mounts, but we could not find the finely-threaded adjustment screws.

Note, SUS decided a while ago (and TMS followed suit) that the ECD copper blocks would not be used at this stage.  The magnets are still needed on the mass for the weight and balance (and for potential future use of the copper ECDs).

H1 PSL installation

First layer of exterior drywall has been put up on the acoustic enclosure. Insulation has been brought inside the LVEA (wrapped for the moment) for inside the walls.

X1 QUAD3 BLD3 TF comparison

X1 QUAD 03 BUILD 03

Attached are plots of the X1 QUAD 03 BUILD 03 M0 & R0 TF measurements from last night along with measurements from 01/06/2012. For the M0 mass, there is virtually no change in the resonances from the two measurements, which is expected.  The R0 chain, however, is the chain where the cabling attaches between stages.  On R0, all DoFs except Pitch appear to have not been affected by the cable lacing.  The R0 Pitch plot (pg 5) indicates the second major pitch mode has stiffened quite a bit since the 01/06/12 measurement.  The DC Pitch also decreased slightly for this measurement. Cabling between the stages may be the cause of the extra Pitch stiffening on R0, so a reassessment of the R0 cabling could prove useful.

This sort of R0 Pitch stiffening is expected, and acceptable once cables are laced down the reaction chain. See discussion of similar before vs. after lacing on ITMY: LHO aLOG 1769.

I'm actually more concerned about R0 Roll: The second mode (~0.85 Hz) seems to have split, or now has two couplings virtually right on top of each other. We should look into this further! 

Weld repair on VBO

Small weld repair performed on new vacuum bake oven (VBO-D) to repair leak stemming from manufacturing defect in external stitch welds. Cleanliness was maintained including a foiled welding helmet to protect the inside of the oven from contamination and the inside of Slim's head from government mind control rays.

Work done by Slim, MarkD and KyleR.

X1 SUS QUAD 03 BLD 03 M0 & R0 TFs

X1 QUAD 03 BUILD 03

The first set of matlab TFs for M0 & R0 masses on the latest QUAD build (QUAD 3 BUILD 3) with full cable lacing to the lower stages.  The M0 measurement agrees very well with the model for all DoFs, with the Pitch DC adjustment a little lower than the model (as expected from every previous measurement).  For the R0 measurement, the L and T second modes are slightly lower in frequency from the model and with the same lowered Pitch DC level discrepancy, although it is a bit more than the M0 difference.  Comparisons with previous measurements to follow.

X1 SUS QUAD 03 BUILD 03 Diagonalization Results

X1 SUS QUAD 03 BUILD 03

Attached are the Diagonalization test results from yesterday on the X1 QUAD 03 BUILD 3. The build now has the full lacing of cabling down to the lower stages on the R0 chain.  Diagonalization tests were run for the M0 and R0 masses to assess Vertical and Yaw DoF isolation from non-contributing OSEMs.  Results indicate a slight coupling of the M0 F1 OSEM to Yaw about ~10dB isolation. Ideally, at least ~15dB is desired with isolation of at least ~20dB preferred.  All other DoFs for both chains are well-isolated from the non-contributing OSEMs.

M0 Vertical Diagonalization - at least ~31dB isolation from F1, F2, F3, SD
M0 Yaw Diagonalization - about ~10dB isolation from F1 but at least ~30dB isolation from SD, LF, RT

R0 Vertical Diagonalization - at least ~28dB from F1,F2,F3,SD
R0 Yaw Diagonalization - ~22dB from F1 and at least ~34dB from LF,RT,SD

Vibration absorbers - Stage 1

We performed some tests with the Vibration absorbers of stage 1 with different Vitton pads (identical contact surface and different thicknesses). Measurements done without the vibration absorbers lids.

Parameters Surface: 0.25"x0.25"

Thickness:

- 0.0625"

- 0.125"

- 0.25"

Results:

- Reduction by a factor of 6 of the 217 Hz resonance on X, Y, RX, RY using pads with a thickness of 0.125".

2 measurements (2012 01 06 no vibration absorber - 2012 01 11 6 vibration absorbers)

https://svn.ligo.caltech.edu/svn/seismic/BSC-ISI/H2/ITMY/Data/Figures/Transfer_Functions/Comparisons/

LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_H_to_ST1_L4C_H_20120106_vs_20120111.fig

LHO_ISI_BSC8_Comparison_TF_C2C_ST1_ACT_V_to_ST1_L4C_V_20120106_vs_20120111.fig

- With the thickest pads (0.25") the vibration absorber are less effective

- With the thinnest pads (0.0625"), performances are similar (slightly better)

 

Next step:

- Tests with the lids on

 

Vibration Absorber Viton Shim Swaps

(Corey, Jim, Vincent)

Yesterday (1/24) afternoon, Jim and I went in and swapped Stage1 Viton Shims (these are located under weights) mounted on the Access Walls of Stage1.  We removed 1/16" shims & inserted 1/4" shims.  Vincent will then make measurements on the system to gauge their performance.  (note:  before the 1/16" shims, 1/8" shims were looked at).

plots of dust counts

Attached are plots of dust counts > .5 microns.

Uninstall of HAM6 OMC

Keita, MikeL, JohnM, DanH

We un-installed the OMC and associated cabling, QPDs, and optics from HAM6 this afternoon.  The OMC SUS is currently clamped down and double-wrapped in aluminium foil and AmeriStat on the top level of a rolling cart next to HAM6.  The SUS frame is dog-clamped to a cleaned optics bench on the cart.  We'll crane the whole thing over to its temporary home inside the ISCT4 meat locker soon.

From the top of the HAM6 ISI, the optics, tip-tilts, balance masses, hardware and cables were removed and were wrapped in aluminum and double-bagged in ameristat.  We put everything in five plastic containers next to the ALS table (in the mini optics lab) in the LVEA.  There are many hockey puck weights on the floor next to HAM6.

The components removed from HAM6 and stored in the containers are:

Black glass beam dumps:

3 double-glass V-shaped dumps
2 single-glass dumps
2 L-shaped dumps
1 flat dump (from overhanging the edge of the table)
some small black glass pieces

Tip-tilts:  TT0, TT1, TT2, optics removed.

Optics:

3 mirrors (from tip-tilts, individually bagged and labeled)
3 hi-reflectors: part numbers IP122-32, 33, and 37
1 CVI BS1-45P
1 CV1 mirror
1 CVI mirror-type-thing, with wedge, and with a chip on the side
1 CVI lens, PLCX-50.8-250.5C 

Optic Mounts:

5 2" DLC mirror mounts, one with a bad pitch adjustment (bagged individually, labeled as such)
2 2" lens mounts (one was used for a hi-reflector)

Dog clamps & clamps for mirror mounts

1/4-20s, separated by Ag-plated, SS, and vented SS

OMC QPD1 & 2, with cables, and cable connector bracket

OMC on the move!