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 jig. - 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 process. - 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 come. - 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 frames. - 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.
- 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.
- 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.