interoffice memorandum
to: Persis drell, Robert Johnson, Steve
Kahn, Charlie Young, Albert Nguyen, Dave Rich, Jerome Lepulu.
from: Richard Gobin.
subject: Teledyne production stoppage recovery plan due
to excessive broken traces on lat-ds-00370 rev.6, PITCH adapter.
date: Jan. 6, 2005
an urgent meeting was
held today in bldg. 28 TO discuss the issues associated with excessive broken
pitch adapter traces at teledyne which yielded 0% acceptable mip-1 tmcm’s
Following production start up @ teledyne.
Ateending the
meeting:
persis drell
steve kahn
charlie young
robert johnson
richard gobin
charlie young reported
results of the second effort at teledyne to attach ds-00370 pitch adapter to
the bare pwb’s on wednesday, january 5, 2005.
this effort included
four ddi bare pwb’s which were not deburred at slac.
this effort also
included four pitch adapters. two pitch adpaters were manufactured at parlex,
the results of the
flex attachment are documented in trip report dated 1-6-2005 from charlie young
& richard gobin. all four pitch adpaters exhibted excessive broken traces
and were deemed rejected. photographs of the four rejected pitch adpaters have
been received from teledyne to slac 1-6-2005.
we believe the
following are contributors to the root cause:
1.
radius of the
bare pwb is not even & controlled to the 1mm requirement.
2.
pitch adapter
3.
pitch adapter
plating thickness of nickel over copper not controlled to the 150micro-inches
requirement per note 5 on dwg. lat-ds-oo370 rev.6
4.
the 1mm radius
has little margin for process variations present with each production run.
5.
uneven pitch
adpater attachment across entire length of flex due to teledyne bending fixtures
(3mt1601210 1-4) OR radius of pwb stiffener.
action:
1.
diamond tool
& die pwb radius control early vs. late: ( rg/dr/cy)
2.
section pwb at
‘good’ & ‘bad’ locations. (cy)
a.
measure radius
b.
robert kirby
3.
new fixturing
i.e. compression vs. tension (cy/rj)
4.
review mechanical
drawings to determine if pwb radius can be relaxed to >1mm. (rj)
5.
provide tool
radius tool history from diamond tool & die. (d.rich/RG)
a.
recall the 12
routers used.
b.
history of all
pwb’s.
6.
purchase
additional dyconex pitch adapters (rj/J. tice)
7.
slac to manufacture
aluminum mandrel/fixture to <1mm, 1mm & >1mm radius. (cy)
8.
measure pwb
radius exhaustively. (CY/RG)
9.
gather plating
thickness measurements from parlex, san jose & dyconex, SAwitzerland
(rg/cy)
10.
photo’s of failed boards at teledyne. (rg)