(Corey, Greg, Jim, Vincent) This work occurred from roughly Tues-Fri of this week
Our Seismometer Sensor Issues:
GS13's:
The small cable feedthru flanges on 5 (of 6) GS-13 Pods for the BSC8-ISI were installed with incorrect hardware. To not risk possible future vacuum leaks, it's been decided to swap out these (3) Horiz & (2) Vert GS-13's.
Trilliums:
The pressure sensors inside the vacuum pods were not operational for all (3) Trilliums.
Another Galled Bolt From GS-13 Installation
On the first GS13 (Vert @ Corner1), 1 (of 3) 1/4-20x3" bolts galled and broke; see attached photo for the broken stump. This shouldn't prevent re-installation of the new GS-13, but now this GS-13 will have one less bolt to secure it down (which will make it similar to the Corner3 Vert GS-13 on this same Unit!). Alas, this is an ailment bound to happen when installing / removing / Installing / etc. etc. Seismometer Pods.
Reaming GS-13 Pod Bases
Just before we were set to install a new Vertical, Jim remembered ALL Pod Base dowel pin holes are undersized for our dowel pins! So, this meant we had to stop work, get reamers, and do some on-the-fly reaming, before installing Pods.
Drop Tested GS13's
Because the Test Stand and Cleanroom are non-user-friendly, we had to come up with ways to lift the GS13s up to the ISI. The GS13's were initially put on a pallet and were going to be lifted via the forklift. Unfortunately, the first attempt at this caused the GS13's (S/N 77 & 103) to be dropped a small distance (~1ft?)---basically we used a flimsy pallet, and when the pallet was lifted, it tipped, and the two GS13's fell to the ground.
We ended up heaving the Pods up to the ISI by hand.
And Here We Are, Yet Another List of GS13 Locations.
Corner1
- Horiz: 33
- Vert: 79
Corner2
- Horiz: 31
- Vert: 94
Corner3
- Horiz: 16
- Vert: 26 (installed previously)
New Set of Trilliums Installed
Since we received these this week, these monsters were also installed. Here are the S/N's:
- Corner1: 32
- Corner2: 20
- Corner3: 19
For bookeeping's sake, here are the Seismometers which were removed/dropped that are being sent back to LLO:
GS13: 68, 76, 84, 85, 89, 77(dropped), 103(dropped)
Trillium : 12(dropped) , 26, 36
Note On Connectors
All of the connectors for the GS13's, Trilliums, & L4C's, which were disconnectd for this swap, were re-connected, but we didn't screw them to their Pod plugs this time. In case any of these Pods fail, we don't want to deal with the tiny screws for these connectors more than we have to (due to cross-threading/galling issues we've seen before). We must make sure all connectors are securely screwed down before installing an ISI into a BSC/HAM chamber.
Trillium Door Weights
Have noticed a few of these door weights being installed with the helicoil tangs still in place (or the helicoils not installed at all); the helicoils are generally in the D0902614 Trim Masses. Found that one of our bolts came close to seizing in one of these weights (looks like a tang was mauled in the threads). I did not reinstall these door weights because we will need new long bolts to clamp them together (the previous bolts are too damaged to re-use).
