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FDC Weekly Meeting

Date: May 28, 2009

Participants: Daniel, Beni, Bill, Eugene, Brian, Simon, Fernando, Mark I., Mark S., Roger, Chuck

Next Meeting: June 4, 2009 @ 1:30 p.m.

Full-Scale Prototype Updates

 - Cathode Board Orders
    * Cathode boards: There were delays in the cathode board construction
      that were not fully communicated to us. It seems apparent that the
      company (Allflex) had some yield problems and has run out of 
      both the 2 micron and 5 micron Cu material. They will only be able
      to complete half of our order. The order is nearly 3 weeks late and
      we have been told that they will ship what they have to us tomorrow.
      We can expect delivery early next week.
    * Rigid-flex assemblies: Delivery is expected next week. We will arrange
      for soldering of the preamp card connectors and the addressing 
      resistors after board arrival.
 - Chamber Wire:
    * No update on completing the SEM studies of our wires. Brian will 
      prepare a final QA report with photos and test results for all wires 
      when all studies are complete.
 - Soldering Work: 
    * Soldering work began on the wire frames (what we call Phase 2). The
      technician (Armen Stepanyan) was supplied from Fernando's group.
      After essentially completing the work on the first wire frame, it
      was decided that we just did not have the right tools for the job.
      Fernando will prepare a purchase requisition for a proper soldering
      station and will order stencils for soldering on the preamp card 
      connectors. We will also replace the Mantis magnifier with a better
      system that Fernando's group will supply. He will put a rush on the
      order so that it is available next week.
    * Roger reported that the apparent problems we had with the height of
      the solder on the rigid-flex assembly solder test was due to the fact
      that we were testing with a recycled assembly. He believes that this
      will not be an issue for the new boards.
    * Fernando has finalized the resistor values for the preamplifier card
      addressing resistors. When we recommence the Phase 2 soldering work,
      we will put the resistors on the frames.
 - We are sharing the clean tent with Hall B.  The Hall B folks have had
   some setbacks and will need another 3 to 4 weeks to complete their
   work. So far, no space conflicts have come up (because we are not
   working in the tent). If a problem develops, we will address it. 
 - Bill has finalized the drawings for the gusset rings that go on the
   upstream and downstream faces of each package to help provide the gas seal.
   The drawings have been submitted to the machine shop.
 - Bill will make sure that we have the appropriate pins for the construction 
   jig. He has completed a design plan for stack assembly and will submit
   his drawings to the shop this week.
 - Brian agreed to start a draft of the stack assembly document. This 
   document should be in place before we get too far in the construction 
 - We discussed a plan for storage of all FDC frames to prevent warping.
   We modify two of our 5-mm thick G10 annuli to include the frame bolt
   pattern and use these as a clamp for the full stack. The stack of
   frames then can be hung on the wall.
 - The mechanical prototype consisting of a cathode sandwich, a wire frame,
   and a spacer ring has been prepared including the cooling loop and
   preamp cards. After review of this layup, we were satisfied with the
   system design and will use this for the full-scale prototype.
 - Cable preparations:
    * The order for the LV cables have been out for a few weeks.
    * The HV cables are in hand and we are awaiting the connectors before
      Mark and Brian begin construction.
    * The signal cables and connectors are in hand and Mark and Brian will
      begin construction as they have time.

Wire Frame Update

 - Mark S. drove to IUCF last week and brought back our 4 completed wire frames.
   See his trip report for full details of his adventure (including talking 
   to strangers). Important details on how to transport the frames to avoid 
   broken wires are provided. No wires were lost in the trip back to JLab. Great 
   work Mark!
 - IUCF has provided us with a write-up/post mortem for the Phase 2 work.
   After the meeting they provided an updated version. They are now working
   on the budget for Phase 3 (production winding). This will be sent to us
   first thing tomorrow at the latest.
 - We will set up a Phase 2 close out meeting tomorrow at 11:00 a.m. with 
   IUCF. We will be discussing plans for Phase 3 and needed work that has
   to happen before then. 
 - We are pushing hard to begin wire frame construction early next year and
   begin wire winding before the end of 2010. Hopefully this can all procede.
   We are now working to complete the simulation studies with Simon to
   determine if we want to offset neighboring wire layers. More to come in
   the upcoming months.
 - Bill will send Keith some information on which sections of the wire
   winding procedures document needs input from them to filling in holes.
   The start of this procedures document is included in Bill's IUCF trip 
   report (GlueX-doc-1229).
 - Bill has been updating the wire frame construction document based on 
   lessons learned from the prototype frames. The file is located 
   at /u/group/halld/Engineering/PRELIMINARY DOCUMENTS. He will include
   the information from Brian on the wire electroplating.
 - Bill is now designing the jig for the wire electroplating operation
   and it will be ready for submission to the shop at some point in the
 - Eugene is working to identify clean room space for FDC construction.
   He is in discussions with project management. More to come.

Cathode Construction

 - Progress updates:
     * The 8 cathode frame laminates and G10 annuli should be coming back to
       us tomorrow according to Bill.
     * Other JLab machine shop work: The aluminum clamp ring for the 
       tensioning facility will have its I.D. increased to give better
       access; One of the G10 tensioning rings will have its I.D. increased
       and will get a skim cut to remove old glue and Kapton; the thin G10
       rings that make up the remainder of the cathode frame laminates will
       have all the through-holes and gas holes added.
     * Bill has been working on the cathode construction document. He will
       circulate a draft shortly.
 - The company that makes our 2 micron Cu board material has already ended 
   production of this line. They may be able to do one more production run
   for us given the significant amount of material (~1500 ft) that we are
   after. We are working to convince the company (Nippon Steel Chemical Co.)
   to complete this run for us. DSC is preparing a letter to send to the
   company to help convince them to complete a run for us. Stay tuned.
 - Roger needs to prepare a document for QA/stuffing/cleaning for the
   cathode boards and a similar document for the cathode daughter
   boards and ground boards.
 - Mark noted a problem with clamping the 5 micron cathode board to the rock
   of the flatness measuring system. Bill is preparing to mount a ring on
   top of the frame. Mark will then complete the measurements.
 - Due to the shortage of cathodes from Allflex (delivery should be 1 
   5-micron Cu board set and 3 2-micron Cu board sets), we will have to
   make a cathode out of the 2-micron board set current in the tensioner.
   This should be O.K. as this board looks good. We will have to check the
   board distortions once it is tensioned.
 - The plan for cathode construction next week is to do electrical QA on
   the boards and then cut all edges. Brian and Mark then plan to work
   on preparing the panel lay-ups one after the other while tensioning
   the boards in parallel.

Cooling System Tests

 - Fernando is in the process of writing up the results from his cooling 
   system studies.  Stay tuned for the GlueX note. He indicated that he
   is back to work on this document and it should be done shortly.

Cosmic Ray Test Stand

 - We have moved the FDC cosmic ray test stand from the Test Lab back to the 
   EEL building early. Beni is working to organize the equipment and will
   work with Simon to start putting it back in working order.
 - We still have some mysterious behavior with the small-scale prototype
   response with wiggles in the X vs. Y distributions that need to be
   understood. We decided to have a separate meeting to discuss what work
   we would like to do on the small-scale prototype.
 - Beni has started a bench test plan for the full-scale prototype and
   we discussed his preliminary document briefly. He will circulate it
   for feedback and we will continue to flesh it out. We want to make sure
   that we do some checks of gas leakage with the prototype. We agreed that
   the best procedure would be to use the P5 gas mixture (non-flammable).
 - Bill has designed a system to rotate the prototype from vertical to 
   horizontal. The drawings will be submitted to the machine shop shortly.

Work List

 - The FDC short-term work list has been posted on the FDC web site.  
   This is continually being updated and DSC welcomes any feedback or 
   comments from the group.

Minutes prepared by Daniel. Send any comments or corrections along.