Difference between revisions of "Minutes-8-6-2009"
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- Beni has started a bench test plan for the full-scale prototype and | - Beni has started a bench test plan for the full-scale prototype and | ||
is presently working on it after incorporating feedback. The current | is presently working on it after incorporating feedback. The current | ||
− | information is contained on the [http://www.jlab.org/Hall-D/software/wiki/index.php/FDC FDC wiki page] under the heading "FDC test cosmic ray test stand". | + | information is contained on the [http://www.jlab.org/Hall-D/software/wiki/index.php/FDC FDC wiki page] under the heading |
+ | "FDC test cosmic ray test stand". | ||
- The parts for the support/rotation of the full-scale prototype in the | - The parts for the support/rotation of the full-scale prototype in the | ||
cosmic ray stand will be assembled as we have time. | cosmic ray stand will be assembled as we have time. |
Revision as of 15:31, 6 August 2009
FDC Weekly Meeting
Date: August 6, 2009
Participants: Daniel, Brian, Bill, Beni, Simon, Rich, Fernando, Mark I., Mark S., Eugene, Roger, David, Micah, Chuck
Next Meeting: August 13, 2009 @ 1:30 p.m.
Contents
General Announcements
- Today was Rich Rines last day with us. The Hall D gang wants to thank him for his hard work on the FDC project this summer and to wish him well on his studies at UMass.
General Construction Updates
- The parts for the assembly jig on which the detector stack will be constructed will be put together as there is time. This should probably happen in the next week as it has been moved to our short term work list. - Bill has begun work on the FDC stack assembly document. The draft will be made available after he completes a bit more work on it. The document will be fleshed out during the assembly process with relevant photographs. - The composite frames for the two gas windows have been completed. Sealing of the I.D. and O.D. of the frames has been completed, with the sealing of the bolt holes remaining. The tensioning of the gas windows and the lamination to the composite rings will be done as we have time in the next couple of weeks. - Mark S. has begun construction of the ground cable pig tails that will be used to attach to the cathode planes. He will make up about 20 of the cables initially and make up more as they are needed for the full-scale prototype construction. - A final decision has been made on the conducting epoxy that we will use in the prototype. Mark S. has prepared the order. - We still need to follow up with Steve Christo to find out the status of the wire order and the status of the qualification of the vendors. - More space has been taken in EEL 126 after one of the large dark boxes was moved away. We have set up a humidity-controlled tent in the space as the humidity in the room was measured at about 60-65% (even though our cheap-o Radio Shack devices were reading 40-45%.
Wire Frame Update
- Rich has done what he could to remove the solder from frames P4 and P3 and is currently working on cleaning frame P2. This work should be completed by the end of the day today. He has also been checking over all components on the boards to flag those that are missing, are problematic, or have the wrong value. Armen Stepanyan from the Fast Electronics Group has been coming in and doing the repair work as needed. - Rich has found several HV busses on each wire frame (P4 and P3) that seem to persistently draw about 1 uA of current. Whether this is related to the relative humidity in EEL 126 is unclear. The boards have been cleaned extensively and checked under the microscope for other problems. We decided to dry the frame out in the humidity-controlled tent over the weekend and to retest next week. - The last wire plane that needs checking and repairs is P1. This work will not happen in the short term as only 3 frames are needed for the full-scale prototype and we don't have the manpower to work on this now. - Rich will provide a write-up on his QA check procedures and make this available. - We need to have a dedicated meeting to design what the schedule for work on the Phase 3 wire winding will be. The highest priority for work scheduling will be doing work on upgrades of the wire winding facility. This includes a better strongback design, the design and construction of precision combs, modification to the wire winding table, and a list of other items with the system. Stay tuned, more to come. - The wire frame construction document is located at: /u/group/halld/Engineering/PRELIMINARY DOCUMENTS. He will include the information on the wire electroplating process as well. - The parts of the jig to use for the wire electroplating operation are in our hands. They will be assembled as we find time. - Brian received the SEM scans for our wire from the W&M folks. He will generate a final QA report with photos and test results for all wires when he gets a chance.
Cathode Update
- Progress updates: * One of our completed cathode boards is really contaminated with epoxy near the two seams. The epoxy manufacturer sent us a solvent that they believe should allow the epoxy to be removed. Bill did a test that effectively removed the epoxy by also discolored the Cu surface on his test sample. This was due to the fact that the solvent was not effectively neutralized. Bill will talk to the manufacturer to find out what they recommend. It may be that we can save this cathode after all. * It was found that the cathodes were not sitting flat on the flatness system. Bill came up with a work around that fixed the problem wonderfully. Flatness measurements can now proceed. * Ground planes have been attached to the two transfer rings and one has been mounted on the tensioner. We need to tension this one and use our experience to define the nominal tension. Lamination to the cathode should proceed following by glueing down of the ground flaps and attachment of the ground pigtail. - Micah found a problem with the speed settings and laser head settings on the flatness system and has made fixes. DSC wants to see the nominal set of plots made for a given scan and needs to devise a criterion for cathode flatness acceptance. - Bill is devising a work plan for the prototype construction that he will give to Chuck to put into a schedule for tracking. - The Fast Electronics group completed the soldering and initial QA checks on the rigid-flex assemblies. Fernando stated that the QA checks done were visual only. An electrical QA check is essential and he will come up with a test station and test plan that we can use within the next couple of weeks. - Mark S. will begin test soldering of the rigid-flex assemblies to test cathode pieces to finalize the soldering procedures. He will work under the direction of Roger and Fernando. - Bill has been working on the cathode construction document building in the pictures that are being taken. The current draft of the document is located at /u/group/halld/Engineering/PRELIMINARY DOCUMENTS. We need feedback from folks involved in the process to be sure that all steps are included and accurately detailed. - We are standing by waiting for information on the PR for the 2-um board material. We have learned that the order has gone out, but the Japanese company has still not indicated whether they will fill the order. A second company that can produce the board material has been identified. Roger has been in contact with the U.S. representative of this company and believes that we will have an answer by the end of this month. - 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.
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
- Beni is continuing work to setup the cosmic ray telescope and test system in EEL 126. Progress is slow and steady. Safety paperwork is now in place and gas is flowing to all chambers. We have seen preliminary FADC spectrum from the cathodes and TDC spectrum from the wires on the small-scale prototype. Beni will work to reproduce the "picket fence" plot that Simon has produced to quantify the resolution last year. - 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 is presently working on it after incorporating feedback. The current information is contained on the FDC wiki page under the heading "FDC test cosmic ray test stand". - The parts for the support/rotation of the full-scale prototype in the cosmic ray stand will be assembled as we have time.
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.