FDC Weekly Meeting
Date: March 5, 2009
Participants: Daniel, Beni, Brian, Bill, Simon, Roger, Mark S., Mark I., Eugene, Fernando, Chuck
Next Meeting: March 12, 2009 @ 1:30 p.m.
Full-Scale Prototype Updates
- Clean Room Issues: * The Hall A folks will not need access to the clean tent for the foreseeable future. Bogdan will give DSC advanced notice if their plans should change. - Cathode Board Redesign: * Roger has essentially completed work on the cathode board redesign to allow for the board stretching. He will have the PR to Eugene this week for signature. Roger will send PDF version of the boards to Bill and Brian to see if they would like any additional sighting or fiducial marks added. The plan is to purchase one more pair of complete 5 micron Cu boards and the remainder of the sets (which should be 6 full sets) should be 2 micron Cu boards. Roger will get updated cost estimates from Allflex in the next couple of days. * Roger has a new version of the cathode daughter board with the power connector flipped to the other side. Bill is satisfied now with the clearance and Fernando has to sign off still. This PR should go in the next couple of weeks. - Chamber Wire: * Brian talked to the SEM folks and they will complete their tests when the new SEM is configured in the next few weeks. Brian will prepare a final QA report with photos and test results for all wires when all studies are complete. - Mark S. is also responsible for upkeep of the list of procurements for the full-scale prototypes. * Location: M Drive/halld/Electronics, or for more sophisticated folks, /u/group/halld/Electronics. - A bottle neck in our prototype construction is that we have only one cathode board tranfer ring. A second transfer ring should be in our hands this week. - Procurements: * Fernando completed a PR for two CAEN HV modules, and sufficient HV cable and connectors for the prototype tests and, in fact, the full FDC and CDC systems. We are awaiting signatures.
Wire Frame Update
- Status: IUCF has completed the tension measurements on the first wire frame (labelled P4) after pinning it and bolting it to its support backing. A systematic variation in the tension from one side of the frame to the other is present for both the sense and field wires. It could arise from the wire load and subsequent warping of the frame. Bill will look into this when he is out there. The wire position data has been taken, but the analysis is not complete and will be finished next week. The second frame will be prepared after we look at all the data and give IUCF the go-ahead when their personnel return from travel next week. - Nominally Bill will go to IUCF for the week of March 16. We will meet next week with Bill to go over his work plan for this trip. - Bill has designed a wire frame protective cover that will be in place during the Phase 2 component stuffing. It needs to be test fitted onto our existing wire frame to be sure all is good in the world. Bill has also gather parts 'n pieces for a turntable for the solder technicians to use with the wire frame for this task. - Bill/Mark will update the wire frame construction document based on lessons learned from the prototype frames. A new version will be posted when his work is done. - We plan on performing the electroplating technique with at least a couple of our full-scale prototype wire planes. We will do some more practice on the Phase 1 winding planes to finalize the technique and to prepare a procedures document. A positioning jig will be put together to allow for precision positioning of the deadened region and its size. We will plan on doing optical scans of the plated region to be sure the plated region is very smooth and well defined.
- We reviewed the cathode R&D timeline. Folks are reminded to pass on progress updates to Chuck every Wednesday. The current schedule is being kept on the mdrive at: * Location: M:\halld\Individual-Schedules\FDC or for more sophisticated folks, /u/group/halld/Individual-Schedules/FDC - Progress updates: * Cathode sandwich prototype work: The two cathode mock-ups have been completed and the ground plane has been tensioned and attached. Mark has been attaching the external ground pig-tails to the ground plane and to the "cathode" planes. Folks are satisified with this design. We need to remember to ground both sides of the ground plane. The two cathode frames will be laminated together tomorrow and final mechanical studies will be performed to finalize the cathode frame design this week. * We will use Roger's sample cathode daughter boards with the mechanical cathode sandwich prototype to study the clearance and space between neighboring cathodes. This will happen this week. * Bill noted that he has designed another laminate to attach to the first and last cathode frames that the gas bags will attach to. So even though the first and last cathodes in a package will not be attached to another cathode (thus forming a sandwich), they should still be plenty stiff. * Bill has started work on the cathode construction document. He will circulate a draft shortly with what he has for comments. This will most likely occur after the completion of the cathode sandwich mechanical prototype. Simon has taken some recent photos of the setup that will be incorporated. * The order for additional G10 pieces for the cathode frames has just gone out. It will be about 3 weeks until they arrive. We have enough material to make 2 more cathode frames. We will have to get Eugene to negotiate to get these through the shop. We will have to negotiate again when the remainder of the frames are ready for the shop. Bill and Mark S. should communicate with Eugene on when the frames will be done from our side, when they will be ready to give the frames to the shop, and when we need them back by. * Edge cutter update: After playing with the camera and stabilizing it, additional test cuts on our dummy cathode boards were completed. We have declared the cutter ready for business. Bill will modify the blade lever arm to make it easier for adjusting, but we will start cutting the cathode boards tomorrow. We will start cutting our 5 micron Cu boards first. Brian estimates it should take half a day to cut on full panel's worth of boards. * We discussed what we want to make next in terms of the cathodes. It was decided to make a "real" 5 micron Cu cathode board next. We will then move to make our 2 micron Cu boards. * The pieces to hold the cathode frames flat should be ready this week. We will use them with our first "real" cathode board and finalize the procedures.
Cathode Flatness Measuring System
- Documentation of the system continues. See the FDC wiki page for details.
- The spacer frames are now done and we are very pleased with how they came out. Mark will install the Kapton gas tubes on the inlet and outlet when he gets a chance.
Stack Assembly Procedures
- We Bill will work to finalize the stack assembly construction document that has been prepared. This document should be in place before we get too far in the construction process. - Bill has found some plastic threaded rods that could be used to compress the stack. We will be receiving some samples shortly and will carry out some loading tests.
Cooling System Tests
- Fernando is in the process of writing up the results from his cooling system studies. Stay tuned for the GlueX note. - Bill has done some ANSYS modeling to better study the connector that goes from the daughter board card to the cooling loop. These will be added to Fernando's note.
- 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.
Cosmic Ray Test Stand
- We will be moving the FDC cosmic ray test stand from the Test Lab back to the EEL building. This move should be probably take place in April. - 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 would like to put together a bench test plan for the full-scale prototype within the next couple of weeks. This preliminary test plan will be used to provide information on what test stand fixtures to support the chamber we will require. Bill can then work on the design and get things prepared in the shop. Also, we would like to layout a design for the electronics before too much longer so that we can reduce time from when the full-scale prototype is constructed to when we get into the test plan.
- 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.