FDC Weekly Meeting
Date: March 12, 2009
Participants: Daniel, Beni, Bill, Simon, Mark I., Eugene, Fernando
Next Meeting: March 19, 2009 @ 1:30 p.m.
Full-Scale Prototype Updates
- Cathode Board Orders * Cathode boards: Roger is waiting for price estimates from Allflex, but the redesign work is done. The PR will move forward when the quotes come in. A couple of issues were discussed. Bill had asked for a reference line be included on the board after the last strip to help with the edge cutting. He wanted the gap between the last strip and the reference to be double checked in the model. Fernando has not gotten the board files for final check out. As we have been cutting the cathode board edges on our first order, several areas on the boards showed the copper was eaten away. Mark will take photos and pass them along to Roger for discussion with Allflex. Perhaps a flaw in their cleaning process? * Cathode daughter board: The board is design is done and checked. Roger is waiting for a quote before sending the PR to Eugene. DSC asked for 60 cathode daughter boards and 6 cathode ground boards to be ordered. - 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 second tension fixture ring has been completed and now in our possession. This should help to reduce bottlenecks.
Wire Frame Update
- Status: We have now received data from the tension and position measurements. Things are fairly reasonable, and we are, for the most part satisfied. There are some systematics trends of both the wire tension and position near one end of the plane and IUCF is now looking into this. We are planning for a teleconference tomorrow afternoon. The wire gluing on frame 2 will be done today and the soldering will be done tomorrow. The frame will be measured next week after the table is wound for frames 3 and 4. - Bill will be at IUCF all of next week to document all procedures and to look at engineering solutions to improve the tension and position measurement accuracy. This may be a start to taking ownership of the IUCF wire winding facility at some point in the future. - 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 has been updating the wire frame construction document based on lessons learned from the prototype frames. He is working to incorporate some more relevant photographs. 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. However, nothing has happened on this front during the past week.
- 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 mechanical prototype is now complete and we are satisified with its mechanical strength. When the frame is lifted, it warps into a potato chip shape on a scale of about 4 to 6 inches. When it is set on a flat surface, it relaxes back into a flat shape over a time scale of several seconds. We believe that we have a complete cathode design that will work for the FDC system. On to cathode frame construction for the full-scale prototype!! * 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 next week. * Bill has designed another laminate to attach to the first and last cathode frames that the gas bags will attach to. 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 been working on the cathode construction document. He will circulate a draft shortly. * The order for additional G10 pieces for the cathode frames has just gone out. It will be about 2 to 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. * Edge cutter update: Cuts on the 5 micron Cu board side panels have been completed and we are fully satisfied. We ran into a problem cutting the center panels that we are working on now before continuing. As we develop a work around, we have started to cut the 2 micron side boards. All board cutting from our first cathode order should be done by Monday or Tuesday of next week. * After the board cutting, Brian and Mark will start to lay up the cathode panels. It might be that we can make the panels and then roll them up and put them into the storage box. * 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.
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. - Beni will work out a space plan for EEL 126 to make sure that we have room to move in our test stand and get it set up and working before we need it for the full-scale prototype. Eugene will talk about the EEL 126 space needs through this summer with Dennis.
- 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.