Minutes-5-26-2011

May 26, 2011 FDC meeting

Agenda

1. Production (Dave)
   • HVAC status
   • Cathodes
   • Wire planes
   • Other
2. Engineering (Bill)
   • Pin rail modification: CMM measurements
   • Rigid-flex gluing
   • Other: encoder, parts/tools for chamber assembly
3. Electronics (Fernando, Chris)
   • Update
   • Package grounding scheme
4. Chamber testing (Beni)
   • Equipment for Blue Crab
5. Other

Minutes

Participants: Eugene, Bill, Dave, Chris, Simon, Beni, Caleb Massey (summer student) and Lubomir.

Production

- Dave: HVAC didn't work starting Tuesday evening (likely), and today Ron Bartek replaced a fuse in line with the transformer that failed before, but was replaced with a more powerful one. So, the same problem again; people from the clean room company will be there next week. Wednesday and Thursday morning the humidity was 50-60% and all the gluing was postponed.

- Cathodes: two ready, except gluing the daughter cards to the frame, that will be done today (conductive epoxy to the copper surface and Scotch-weld epoxy on the sides). Third one is ready for gluing the rigid-flexes. The fourth has been tensioned and the frame glued. Fifth cathode foil is ready, as well. End window: Anatoly is finishing the first one.

- Wire frames: the two wires of the first wire frame were fixed. We will keep it on the table to study the sensor problem: today we had problems not only with the field wires, but also with the sense wires. Dave will coordinate with Ron Bartek how to turn off the AC units to study the vibration effects. Caleb will work on this problem. Eugene pointed out that before trying to mitigate the vibrations we have to make sure that they are the origin of the sensor problem.

Engineering

- The second modification of the pin rail was successful. Results from CMM measurements of the front pin positions are shown at page 567; the width of the distribution is 10u (sigma). New dowel pins were put on the rail to make sure the two parts of top plate can't move. Bill will install monuments on the table and strong-back that will help fixing wires. Today we had to align the strong-back so that the new replaced wires are parallel to the rest.

- The new tool for gluing the rigid-flexes works reliably only with the tinned flexes. On the first two cathodes we used tinned ones, except at two places. Bill thinks it is the new foot that has to be modified to fix the problem, and will try to do it a.s.a.p. After that we will make again several samples and also work on the testing cathode to investigate the problem. Eugene insisted that before continuing with the production we have to make sure the tool works as before. All the samples that we investigate before were made with the old tool, that in principle we can also use but we had some problems with the foot attachment.