Minutes of the Tracker Meeting
December 4, 2003
- Summary of yesterday's engineering meeting
- Results from inspections and measurements in Italy
- Sidewall coupon testing issues, Ben Rodini's requests, etc.
- Plan for testing at SLAC the 120-degree countersink idea
- T/V test preparations, Jack's travel plans. . .
- MCM preproduction status, pitch-adapter attachment test, etc.
There was some discussion of the engineering work going forward on the flexure-grid interface. See the web page http://www-glast.slac.stanford.edu/Tracker-Hardware/ART/vibe/vibe.html for the latest. Sandro, Riccardo, et al will review the SLAC sketches and send their own suggestions on Friday.
Tom will start looking into getting more precise shoulder bolt made, so that the clearance between bolt and hole in the Grid can be closed up.
Sandro emphasized that he would like a steel or titanium sleeve in the grid, to support the shoulder of the bolt. He suggested to do a mock-up the joint and do a pull test to see if the grid is damaged.
Sandro mentioned the possibility of a helicoil with a locking feature.
No measurements were yet made on the new fixture. The fixture was changed out, replacing the damaged one with the new one, and they are going forward with the ESPI test on the tower.
They inspected the old vibration fixture. There was no visible damage to the helicoil. Also, it looks like all threads were used except about 1.5, so the thread engagement was not as bad as Tom thought.
Robert said that he will send two PWBs with pitch adapaters attached at Teledyne with Ronaldo, to be inspected in Italy for wire bondability. Also, the bias circuits will be sent with Ronaldo if Parlex gets them to SLAC in time. Parlex had issues with their plating processes and is a couple of weeks behind in delivering the bias circuits.
Pisa will select honeycomb samples to send to SLAC. Tom suggested to ship them with Elliott or with Luca/Ronaldo in the SLAC case that is already over there.
Sandro confirmed that in the vibration test, the torque in the side flexures only decreased from 2.9 N-m to 2.5 N-m on two separate flexures in slots +X and +Y. There was no complete loss of torque in the side flexures.