Minutes of the December 18 Tracker Meeting
1. Pisa: check on G&A availability for a January 16 meeting.
2. Pisa: mail to SLAC a schedule for completing sidewall coupon testing at Plyform.
3. Hytec: complete analysis for support of the flexure/Grid interface design.
4. Robert: circulate a draft agenda for the January meeting, for comments.
5. Jerry: QC bias circuits and ship to Italy before Christmas break.
6. Jerry/Robert: review bias circuit copper weight on the previous prototype.
- review logistics for the January meetings
- status of Plyform coupons
- painting sidewalls of EM
- review action items from yesterday's meeting on the flexure-grid interface (see below)
- discussion of goals of the January meetings and preparation needed
- bias circuit status
- trip to Plyform to close mid-tray production issues
There was a discussion of the plans for meetings the week of January 12. The TKR team meeting will be January 13 and 14, and we will try to arrange a meeting at G&A on Friday, January 16. Ronaldo or Sandro will let SLAC know asap whether G&A will be available that day.
Riccardo reported that Plyform made 6 sidewall insert coupons yesterday. He needs 20 M2.5 inserts. Jeff will get them shipped today. The new strength coupons are not yet machined. Plyform will test them after Jan 7. Ronaldo or Riccardo will email a schedule for this tomorrow
Jack reported on his trip to Italy for T/V test planning. He was with Tom McCarthy at meetings in Pisa. They determined that a thermal blanket is not enough to isolate the tower, so they will devise a temperature controlled shield around the tower. Jack will send a schematic for the T/V setup to Italy the first week of January. The trip to Alenia was productive. They talked to the manager of the facility and looked into the chamber. It is overkill for our kind of test but will work. He emphasized the need to coordinate who is supplying what. He has a list that he will share with us. We affirmed that Nicola is in charge of test preparations and execution.
Jack said the he does not want the sidewalls painted on the EM. All agreed.
Erik agreed to push to get analysis done in support of the flexure-grid interface redesign.
There was a short discussion of the goals of the January meeting. Robert will circulate a draft agenda soon for comments. Nanda said that he would like to include in the discussion the bigger points of the various manufacturing readiness reviews.
Jerry reported that 39 bias circuits are arriving tomorrow from Parlex. SLAC will QC and ship them to Italy tomorrow. Jerry said that the 1/4 oz copper has caused Parlex a lot of trouble.
Jerry claimed that the prototype bias circuits had 1/2 oz copper, not 1/4 oz as was specified in the drawings. Robert was concerned then that this invalidates the tests that Sandro carried out on the last few EM trays. Robert would like to review this and analyze the previous circuits to determine for certain what we had.
There was a discussion of how to close Darren Marsh's issues for start of flight tray production. The goal is to get this done shortly after the January meeting. Ronaldo said that we need some healing of our relationship with Plyform before doing that.
Action items from the Wednesday engineering meeting:
Analysis of EM test data. Inspection of bottom tray? Tom V thinks that the big failure will hide any other information. Nanda: come up with inspection plan.
1. NORDBY/FOSS: Complete details of Flexure-Grid Interface
1.1. draft angle of 1 or 2 degrees in Flexure holes to ensure easy disassembly of joints
1.2. reduce chamfer at lower edge of Flexures
1.3. with Tom Borden's concurrence, modify design to move lower edge of Flexures up by 500 microns
2. BORDEN: Develop and validate prototypes of the Interface joints
2.1. Conical pin-hole mechanism
2.2. Liquid shim pin mechanism
2.3. Non-concentric bushing mechanism
2.4. Locking mechanism(s)
2.5. Lubrication of threads or plating to aid in torquing the screws
Martin Nordby (as well as others) will email Tom Borden with a list of the specific action items he thinks is needed.
3. BORDEN: Develop and validate prototype for the Tooling to bore the conical holes in the Flexures
4. KU/SWENSEN: Complete details of the analysis of the Interface
4.1. Estimate stresses and safety margins in Flexure collars
4.2. Estimate compliance of epoxy shim from previous testing and carry out a dynamic analysis to establish safety margins in mid-spans and corners