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FDC Weekly Meeting

Date: May 21, 2009

Participants: Daniel, Beni, Bill, Eugene, Simon, Mark I., Roger

Next Meeting: May 28, 2009 @ 1:30 p.m.

Full-Scale Prototype Updates

 - Cathode Board Orders
    * Cathode boards: The cathode boards should delivered any day now. Roger
      is awaiting word on the shipping date from Allflex.
    * Rigid-flex assemblies: Delivery is expected within two weeks.
 - 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: 
    * We will be looking to Fernando's group to do as much of the soldering
      work for the full-scale prototype as possible as Greg Arnold has told
      us his group is not available. We have soldering work on the wire
      frames, cathodes, and rigid-flex assemblies.
    * To avoid concerns with melting the epoxy on the cathode boards during
      soldering of the rigid-flex assemblies, a test was carried out. There
      were no problems whatsoever mechanically. The issue was the lack of
      control of the height of the solder joint. This needs to be looked into
      to develop better controls.
    * Fernando was asked to finalize the component values for the preamp
      card addressing resistors for the wire frames and cathode frames.
      This work is in progress.
 - We are sharing the clean tent with Hall B.  The Hall B folks will need 
   about 2 weeks of time to finish their work. We need to work out a 
   reasonable schedule for our work in the clean tent to be sure that we have 
   no conflicts with FDC work.
 - The order for the o-ring material for the full-scale prototype has been
   completed.  We have also made sure that we have enough of the epoxies, 
   syringes, and applicator tips that we nominally use.
 - Bill is working to finalize the design of the gusset rings that go on the
   upstream and downstream faces of each package to help provide the gas seal.
 - Bill will make sure that we have the appropriate pins for the construction 
 - 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 
 - DSC discussed frame warping problems that have been witnessed in our wire
   boards and our spacer rings. It may be that we will have to control the
   storage environment and it may be that all frames will have to be stored
   flat with weights on top. More to come.

Wire Frame Update

 - Status: IUCF has wound the fourth frame and completed tension and position
   measurements. We have received the data. It looks like the systematic wire
   position trend (deviation from nominal position) is still present. We will
   talk to IUCF more about this shortly. It is not clear what is going on as
   the trends that we saw seemed to be attributed to the Moire mask. More to
 - IUCF is now working on the budget for Phase 3 (production winding). This
   will be delivered to JLab by the end of May (the end of the contract).
 - We will set up a Phase 2 close out meeting next week with IUCF. Details
   to come.
 - Mark S. drove out to IUCF yesterday and is picking up the 4 wire frames
   today. They should be here tomorrow for inspection.
 - 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 newest version is located 
   at /u/group/halld/Engineering/PRELIMINARY DOCUMENTS. Please read it over 
   and give him feedback.
 - Brian will gather all the bits n' pieces for a write-up on the wire
   electroplating and post his document on the mdrive for feedback.
 - 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
   future. He will get back to this work after the tagger review is done.
 - Mark and Brian completed work on the turntable for the soldering techs.
   This system has a magnifier mounted across it. Protective covers for
   the wires are ready.
 - Mark found that our the rigid-flex assembly solder clearance slots on
   the back of the fifth wire frame that we have (with the solder mask
   boards) had very noticeable non-uniformities in the depths of the slots.
   This problem has been verified to not be an issue with the "real" wire
 - We are starting to consider moving up production winding to the end
   of next year. DSC and Eugene are now in discussions.
 - Apparently the deal to carry out construction of the FDC in the clean rooms
   at Hampton fell through some time ago. Right now, there is no allotted space
   at JLab for construction. Eugene is looking into this now to figure out what
   we will do.

Cathode Construction

 - Progress updates:
     * The 8 cathode frame laminates and G10 annuli should be coming back to
       us very soon. Bill will check into this.
     * 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. Roger is taking charge of this.
 - Roger visited Allflex last week and took us through a slide show of 
   construction of one of our cathode boards. It looks like the company has
   taken our feedback and made improvements to the system that have had
   tangible impacts on our cathode QA.
 - 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.

Cathode Flatness Measuring System

 - Documentation of the system continues. See the FDC wiki page for details.
 - Mark noted a problem with clamping the 5 micron cathode board to the rock.
   It seems that warps in the frame appear between the clamps. Bill will
   look into this.

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 is starting to think about designing a system to rotate the prototype 
   from vertical to horizontal.

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.