Technical Specifications for the Cathode Strip Panels
Nelson led the discussion for the specification document for the Cathode Strip Chamber Panels.
The  DRAFT of the document has been distributed by Nelson. The final Version will appear on these pages.  The following represents the major points and action items that were discussed.

Jump to Conclusions
 
 

• Section 1.0
• O.K.

• Section 2.0
• O.K.
• Response on Last Meeting Action Item:     Measurements at  IB4 on the panels we received so far started today.
• Section 3.0
• PLASCORE proposed to fill the splice gaps on the edges of the panels to make them gas tight. However, since those "fillings" are removed when we cuts the panels to dimensions, it was agreed that the step was useless, and it was removed from the specs.
• Response on Last Meeting Action Item: PLASCORE agreed to characterize the PC and keep the same composition  throughout the production (Fax to Dave)
• Response on Last Meeting Action Item:  It was determined that the numbers we used previously (220 psi for compressive strength and 80 psi for shear strength) are typical values. The Minimum Values that PLASCORE can assure are the ones in the spec (150 psi and 50 psi respectively).
• Section 4.0
• We received a copy of the epoxy specs. We didn't learn much. The epoxy will be specified as an internal PLASCORE product (P88) and, according to MIL-A-25463 we will require it to be Type I (curing at ~180-200 F), Group 2 (
• Response on Last Meeting Action Item: Assuming that the out gassing of the glue in the chamber gas volume happens only through the holes on the panels, and that we don't want the glue to contaminate the gas with more than 1000 ppm O2, Giorgio determined that the out gassing must be below 10-6 Torr liter/cm2 sec. Typical epoxies out gas at few 10-7, and therefore we decided not to include any out gassing spec.
• Section 5.0
• O.K.
 
• Section 6.0
• Action Item:   Jay will measure some samples from the panels we presently have and determine the peel and tensile strengths.
• Andrey expressed concern over the possibility of panels to bow when unconstrained. One suggestion was to ask the panel to be flat under its own weight. Unfortunately we don't know the amount of "bowing" of the panels in the assembled chambers (P1 and P2). It looks however that if there is any bowing of the panels in the final configuration, that is a chamber engineering problem that must be solved, for instance, with extra spacers.  In any case, IB4 will check the "unconstrained" flatness on the panels we already have.
• Action Item:    IB4 (Bill Pritchard) will make some flatness and bowing tests on the approx. 15 panels presently at FNAL.
• Section 7.0
• O.K.
 
• Section 8.0
• Presently we are asking PLASCORE to sample only 10% of a production batch (typically 25 panels out of 250) and measure it, and increase the sampling to 100% if more than 3 panels are found to be bad. Mike noticed that in this case the vendor would avoid 100% sampling if 2 panels are bad (i.e. if 8% of the production is not conforming to spec) which is unacceptable given our limited spare quantity (5%).   He suggested   that the initial testing has to be more frequent and the testing frequency may diminish as the vendor and FNAL become confident on the procedure.
• Action Item:    Mike and Nelson will phrase the requirements on the vendor QC in such a way to sample a large fraction of the initial production and a diminishing fraction later on.
 
• Section 9.0
• Response on Last Meeting Action Item:   Dave PLASCORE proposed an increase of  the panels cost by 5$/panel if we want 16 panels in a box.
• At 32 panels/box, we paid 6.25$/panel for a crating:  i.e. 6.25x32=200$/box. At 16 panels/box, we pay 11.25$/panel for crating: i.e. 16x11.25$=180$/box.   It looks like the cost of the box is more or less constant.
• Action Item:    Ron will look at the boxes received so far from PLASCORE and investigate if we could procure them on a competitive bid and ship them to PLASCORE for less money.