Minutes of the Tracker Technical Meeting
September 19, 2003
There was a discussion of difficulties encountered at Plyform with doing tensile strength tests on K13d unidirectional coupons. Riccardo said that he did a FEM analysis of a coupon of only 1 mm thickness and predicted that the coupon would still fail at the glue joint. Tom will try to get COI to send to Plyform drawings of the coupons that they use and the procedure to pull them.
Tom agreed to organize a telecon between COI and Plyform to discuss issues with the strength requirement that Plyform wants to impose on COI for the pregreg order.
Tom said that he will meet with Erik and Ben to discuss what NDE tests are needed for the finished panels.
Tom reported that the mini-tracker is again integrated with the CAL EM and that I&T plans to do tests with the new TEM/PS next week.
Tom requested that Riccardo send pdf versions of all the INFN tracker tooling drawings to him, to archive in Cyberdocs and post on the tracker web page.
Tom reported on CMM results on the recent MCM flex-attach test done by Teledyne. The flatness is good across the MCM except on one extreme end, where there may be an issue of peeling. There is also some peeling at a location in the center of the MCM. Tom suspects that the problem is caused by the trimming wheel. Tom will beep traces that appear to have surface cracking to see if they are conductive and then will send it back to Teledyne, where it will be run through the reflow oven to see if cracks open in the traces.
Tom said that there will be a meeting on the flex-circuit cable interfaces this afternoon. Electrical layout of the cables is on hold pending settlement of all the interface and length issues. In connection with this work, Tom is looking at the side-to-side tolerances on the Omnetics connectors to see how tight the alignment tolerance must be.
The mini-tracker cables for Pisa are ready for testing. Roger Williams will do that today. (Note: they tested good.)
Tom said that he is ordering more titanium inserts for the static test walls. He plans at the same time to order enough for all of the flight towers.
The corner bracket and flexures drawings are ready for review. Sidewall and bottom tray drawings are also in review. The mid-tray assembly drawings are almost ready for review. The no-converter assembly drawings are ready.
Tom will look into obtaining epoxy ink to send to INFN for marking serial numbers onto assembled tray panels. BJ will add this to the materials list. Jerry has already recommended a specific Hysol product.
Riccardo said that they need SLAC to send another 1000g of the Nusil conductive adhesive, to be used for core grounding.
Tom reported that the revised top for the prototype shipping container arrived and looks good this time. He said that they are making from unistrut a dummy tower to put into the container to test it. They are also ordering another environmental monitor for it. They will leave all that stuff in it when they send the container to Italy, which will be an interesting test of the container.
Riccardo requested that Tom and BJ send to him a CD with the tower model and the value for the center-of-gravity location. He needs the latter for his design of the fixture for rotating completed towers.