# Flex review snapshot - 8 September 2026

Upper v0.3 replaces the old wire-solder tail with 30 B-side insertion contacts for
main J2. There are 24 separate zone rails; each of the six positive rails has two
contacts. The front carries the insertion support, and total mating thickness is
0.30 +/-0.05 mm. Contact order is 4,5,6,1,2,3 zones; each group is +,+,W,N,C.
No solder belongs on J100. Upper overall size is 324.968556 x 42.9 mm.

Lower and static gimbal remain v0.2, byte-identical to their prior review.
The 96 upper strip interfaces and retained band routing are unchanged according
to the native preservation audit. Apparently isolated upper strip pads receive
their intended feeds through the lower band and matching real strip through-rails.
Those real rails have not been measured; the assembled topology is conditional.

Fresh upper snapshot checks: zero ERC/DRC/parity/unconnected violations,
independent endpoint-role oracle, 222 copper pad flashes, 252 tracks and 192
drills checked against native geometry. Independent physical-CAM connectivity
and mating audits are separate hash-bound records. Nothing is physically tested.

The old A3 PDF is HISTORICAL: its upper-tail outline is obsolete. Use the current
upper view/template-1-to-1.svg and view/insertion-drawing.svg for v0.3. The old
PDF remains only for reference; do not use it to approve current insertion fit.
The 0.3456 mm tape-tolerance alignment sensitivity still exceeds the nominal
0.30 mm lateral margin. It is a computed fit risk, not a passed physical test.

Full-loop electrical cases are explicitly historical (old upper v0.2 geometry).
The current isolated tail/contact screen is separately bound to upper v0.3:
at assumed 85 C copper, 30 um thickness and the stated width/contact allowances,
the worst loop drop is 0.1044 V. This omits the rest of the strip circuit and
does not predict temperature. Its 0.60 A positive / 0.20 A channel stress cases
are NOT continuous operating ratings. Commissioning guidance remains <=0.50 A
RMS per zone conditional on local fuse air <=85 C and measured strip/PWM loads.

JLCPCB received these designs for engineering quotation; PCBWay flex formal
inquiries remain pending a compatible custom-stack route. No procurement,
payment or production release. Supplier finish, copper, coverlay, insertion
stack and dimensional tolerances remain open, as do physical fit, joints,
enclosure temperature, RF/EMI and system operation.