Minutes of the Tracker
Meeting
July 8, 2004
Action Items:
Status of Alignment
Activitiesa: The CMM was reconfigured to increase its travel range. Tomorrow morning they will be able to try
out the alignment procedure.
Sandro noted that they did
some tests with the cones and found that they could achieve a setting error of
+-10 microns.
Status of SLAC deliveries
for next week:
- Reworked MCMs: 45 returned
from Zentek yesterday, with the new 75 ohm resistors. They are going through testing again and at least 36 will go to
Pisa with Robert on Monday.
- Cable tester: SLAC has 2
units, so Robert will bring one to Italy.
- Lifting fixture: it is in the
SLAC shop and on track for a Friday delivery.
Dave is working with the riggers for a proof load certification on
Saturday. John Ku and Mike Foss are
involved.
- Inner shipping container: it
is at an outside shop and scheduled for delivery tomorrow. Martin noted that this also needs a load
test, since it is also used to lift the tower.
It needs a cable holding plate for assembly. Probably it will ship to Pisa next week, not be hand carried.
- Cable holding plate: there
was a problem with purchasing keeping the vendor on hold. The machine shop is now working on the first
article, which will be available Saturday.
They had to skip the alodyne finish to make that shedule. CMM of this is scheduled for Saturday.
- Interface hardware: 18
sets of studs, cones, and hex bushings are at SLAC. Nytemp is on the studs.
Arthur validated the process and checked the fit and running torque. The studs and bushings are currently out for
Dycronite coating and will be back tomorrow at noon. The M5 hex nuts are complete and will be delivered tomorrow.
- Cable bending tool: the radii
don't look correct. There is an NCR,
and this needs to be evaluated and corrected next week.
- Outer shipping container:
Ku and Foss are working on it with Jeff.
Mike Opie will look at the current load design. They are coordinating with Tom Borden, who
supervised testing of the previous container.
They should email all the info to INFN and Martin Nordby before ordering.
Sandro needs the dimensions immediately in order to size the truck
needed to cart the tower around Italy.
Jeff said it will be ength 37.75" x width 37.75" x height
48.00", all outside diameter. This
keeps the same foot print as the previous container but lowers the height by
11". It was decided that there
should be no castors. Instead, it
should be bolted to a plastic pallet. Jeff
noted that the height leaves 6 inches clear inside the container top and
bottom.
It was noted that we need a
longer battery life for the environmental recorder, which only worked for 4
days last time.
- Corner cable mounting
brackets: the design is just being completed by Foss. A PR was submitted for quotes.
SLAC will pay an expediting fee for the first units, but there is no
delivery date yet. Martin should send the
design info to Chris Fransen.
- heat straps: these are in
fab at SLAC with delivery Friday afternoon; CMM is scheduled for Saturday.
- torque wrenches: Dave procured
a full complement of preset torque drivers; 2 of each. Martin said he still needs to review the
torque specs. Arthur said that we also
need another torque meter.
- Torx screwdrivers and bits
were also obtained.
- M2.5 100-degree sidewall fasteners:
the screws are due tomorrow. SLAC
should keep some for inspections; SLAC should also keep some of the hex nuts.
- The new vibe fixture will
come in later this month; we must use the existing fixture for Tower A
- Dave requested that all
travelers bring shipping cases back from Pisa!
- TQCM: GSFC and Jack insist
that it is needed. Nanda is checking
more in Italy. Can one be obtained from
NASA?
- Reflector balls and nests:
the PR went in yesterday.
Flight cable status: Darren
reported that 16 cables went to INFN. Parlex
could not produce coupons for one cable.
Robert said that the 2nd set really should go to the
electronics group at SLAC and would be non-flight at that point. The plan is to keep both sets in Italy for
Tower-A, to make sure that spares are available, and then ship the ones not
used to Gunther. The 3rd and
forth sets were due July 16 but are delayed a couple of weeks due to various
issues. The coupons will go to Richard Gobin
and then to NASA for testing.
Mid Tray Panel Fabrication:
Sandro reported on the coupon tests at Plyform. The bead blasting with 0.5um texture increased adhesion by a
factor of 2.7 with respect to the old hand sanding process. Monday Sandro will go to Bologna, where they
will prepare tungsten for 1 tray with 0.5um roughness plus a few other samples
with other higher roughness specs. Plyform
will then make 1 more tray and will do more coupon tests. Sandro will also on Monday book the company
for the remaining plates. The company
will need to make a simple tool for the foils to go into an automatic
machine. When they are finished they will
pack them with nitrogen. Sandro will
not know the schedule until Monday.
- MRB for the
Kapton-Tungsten bonding issue: a plan was hatched to hold it in Italy next
week. Ben Rodini is available Thursday
morning EDT.
Bottom and Top Tray Panel
Fabrication: Riccardo reported that the Tower A tray was assembled and measured
last week. He has been reviewing the
results with Martin, and they are improving the metrology procedure. There won’t be time this week, however, to
remeasure the tray, so Riccardo will do it on Monday. From the existing data the flexure positions appear not to be
within the drawing tolerances. After
the remeasure Martin will figure out whether this really is an issue. Riccardo also reported that Plyform finished
the top tray closeout machining. Riccardo
will go tomorrow to G&A to pick up the tooling for top tray assembly. Plyform will assemble it next week.
G&A Tray Integration:
Sandro reported that today G&A should have assembled MCMs onto 2 trays with
a redlined procedure. The modification
is to use a washer and nut on each of the 3 grounding pins. This is needed in order to make good
electrical contact to the ground pad on the front side of the MCM. Tomorrow they will do the assembly of
ladders, followed by wire bonding on the weekend. Luca and Luca will go to G&A on Monday to install the test
setup and execute the test. Tuesday
G&A will do the encapsulation, which then requires a long cure. The following Monday Sandro plans to test
the trays with encapsulation. They will
do a T/V test at G&A to 50C for a few hours, with the tray in its shipping
container.
- drawing and procedure
release: The drawings have been signed off but now need to be modified with the
new nuts and washers. The procedure
document lacks just Martin’s signature, and also will need modification for the
nuts and washers. The tray test document
is in release.
Sidewall Fabrication: a detailed
schedule will be obtained tomorrow from Plyform. Martin noted that we still need Sandro's signature on the
drawings.
EM tower shipping to I&T
and the Tower-A shipping container: we want to leave the existing shipping
container in Italy, so the EM tower will be put into its inner container (which
needs the vibe fixture from the tower mockup) and will be crated with lots of
foam padding.
The mockup tower may be needed
in Pisa through next week. We will review
this after tomorrow's experience.
Arthur noted that he saw galvanic
corrosion between shims and the aluminum grid simulator. He said that we really need coating of the
shims as well as the grid.
Sandro noted that they did
do some measurements of the EM tower before and after vibration. They saw only a 50 micron maximum
deviation. Of course, this was not done
with the standard metrology program being installed this week.