Update on module mounting on staves and stavelets

13/6/11

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1) Status of clean room for next assembly kit2) DC to DC stave

Status of R12 Room Allocated for Stave Construction

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Room infrastructure expenditure.. Replace existing lights to get suitable light levels. Fit extra mains outlet sockets. Extend room vacuum system Fit motion sensor ATLAS to pay half costs (2.5K)

General panorama of room used to be old ‘bulk store’ Stave/stavelet storage

Designed with1.6 meter stavesIn mind. Equipped for 4 items

Mobile working area with control PC twin screens and storage

• Vacuum system designed and hardware on order.

• Remember that one needs 16 distributed stations along a 2.5 meter side• Design based around extruded aluminium section and standard connectors• Only sufficient bits ordered for single side.

• Safety documentation needs to be written.• Laser alignment still needs to be designed.• Stages delivery expected end June early July.• Drawings of granite table expected end of this week so out for tenders ASAP.

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Stage interlock system designed, hardware on order and construction started. (Light curtains, stop buttons, safety relays, etc, etc) Development

may be needed

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Equipment rack on order to house stage controller, interlocks, etc, etc.

Need to write the formal risk assessment. Non-trivial as it has cover all possible failure modes, testing, maintenance etc

• Through table fume extraction design needs to be trialled as holes needed in granite.

• Awaiting drawings of granite (expected end of this week), so that we can go out to tender.

• Stages still expected early July.

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DC to DC Stave Construction• Before construction..• Module stuck into stave frame... No longer being done.

• After sticking..• Hybrid feet no longer anything like thick enough due to increased hybrid to silicon thickness and curl on end of hybrids.

• Problem associated with wire bonding due to the cans of the Dc to Dc boards.• Dc to Dc boards stuck with 2011 +BN. Needed a gap filler!

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• kapton not square on stavelet.

• Now no frame of reference in X or Y for construction. Remember that I have almost no travel in Y to align module to the inter-module gap.

• Nothing on the kapon is anything like good enough. Hence placed by eye!• EOS board held down with a mixture of double sided tape and custom clips( bent paper clips and epoxy) so easy to

remove. Note that back of EOS need more insulation by Peter.

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0.75mm

Previously reported that the 1st module to be stuck onto this stave has started to lift..

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• Could be...• Bad mix of adhesive, poor adhesion to Kapton or silicon, bad epoxy,

bad gap.• Not bad gap because the silicon to kapton gap now measured at about

400 to 500 microns except where the silver loaded epoxy is (170 and more like expected) Obvious from pictures on slide 6 that gap was OK

• Plan to try and remove module and end up with a working item rather than shards! (use a 60micron thick 1 tooth saw)

• Re-mounting will include increased gap because there will be old silver epoxy and old silicon on back of module that I can't remove. Clearly module will need re-testing prior to remount.

• Main suspect bad 4445. I have 2 more tubes of 4445 to decant, so will do that and try new mix to ensure its OK before retry. Awaiting more mixing pots from VWR.

• More 4445 on order (3 tubes) BUT.. Only made to special order and on 12 weeks delivery. NB shelf life only 6 months! Ist modules ever stuck used out of date 4445.

• 2125 epoxy on order from Intertronics. (And now delivered)

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