SiDi128 FR4-R7 — fabrication specification for prototype quotation

Six different FR4 designs, one of each per enclosure; separate Gerber ZIPs.
Material: FR4, 2 copper layers, nominal finished thickness 2.0 mm, 1 oz copper.
Mask black both sides, white silkscreen, ENIG finish. Lid gold artwork uses
matching F.Cu and F.Mask shapes. Preserve both; no copper on inside faces.
All F sides face OUTWARD, including the bottom. Opposite panels are mirrored
intentionally in native KiCad coordinates so exterior legends read correctly.

DIMENSIONS / ROUTING
Base and lid: 133 x 133 mm. Overall height: 33.6 mm, unchanged from R6.
Both have twelve matching CLOSED slots; no slot may be opened to an edge.
Bottom tabs terminate 0.2 mm above the underside, inside the closed slots.
Top tabs terminate 0.2 mm below the lid exterior. Both ends capture the sides.
Slot width 2.4 mm for nominal 2.0 mm panels: 0.2 mm nominal clearance each face.
Slots 10.6 mm long x 2.4 mm wide for 8 mm wide tabs with radiused corners.
Minimum outer retaining web beyond both sets of slots: 1.0 mm. Confirm routing
tolerance and strength with the supplier. Do not widen slots into these webs.
From FR4-R6 replace only the lid. Retain all five other panels.
The lid has only four M2.5 fixing drills; the three VESA access drills are
removed. Preserve its vents, tab slots, gold artwork and countersinks.
Minimum window corner radius 0.6 mm; microSD radius 0.8 mm. No plated routed edges.
Do not add copper planes, alter port openings or put order IDs on visible faces.

BASE AND LID REQUIRE EXTERIOR CONICAL COUNTERSINKS
Each has four M2.5 fixing holes: primary NPTH diameter 2.9 mm, major diameter
4.8 mm, 90-degree included angle, depth 0.95 mm from the F / exterior face.
Nominal FR4 remaining at the base/lid bore is 1.05 mm (0.85 mm at 1.8 mm
actual base/lid thickness). Side panels require 2.00 +/-0.05 mm for the pockets.
Match actual screw heads and confirm depth/diameter tolerance in CAM review.
The three 4.6 mm VESA clearance holes in the BASE are NOT countersunk.
There are no VESA access holes in the lid; mounting requires lid removal.
The four SIDE panels have no screw holes or countersinks.
Each fabrication ZIP includes COUNTERSINKS.csv, countersink-locations.svg and
READ-ME-COUNTERSINKS.txt. Side tables are empty intentionally. Gerber/Excellon
alone does not encode countersink depth or angle. KiCad Dwgs.User marks majors.

CONTROLLED-DEPTH POCKETS — REQUIRED
Eight existing pockets from B / inside, R0.60:
- Front: SW7, SW1/SW2/SW3, 1.00 mm deep.
- Rear: J1/J4 audio 0.60 mm; SW6 input switch 1.00 mm deep.
- Right: J7 LAN 1.30 mm deep. Left: none.
One pocket from F / exterior, R0.80:
- Front: J9 mini-USB shoulder seat 11.80 x 9.30, depth 0.65 mm.
  Central through hole remains 8.60 x 4.80 mm, R0.60.
  Nominal remaining skin at seat floor is 1.35 mm, minimum 1.25 mm.
Side finished thickness 2.00 +/-0.05; all pocket depth +/-0.05;
pocket/profile finished edge +/-0.10 mm. Minimum skin is at LAN: 0.70 mm
nominal, 0.60 mm minimum. Inside pockets and J9 exterior seat do not overlap.
All pocket regions have no copper. Review exposed FR4 recess floor finish
with the supplier; ordinary routed walls/floors are not black solder mask.

Each ZIP includes BACK-POCKETS.csv / FRONT-POCKETS.csv, matching location SVGs
and READ-ME notes. Empty tables explicitly mean no pocket of that type.
Coordinates use native KiCad F-view X/Y; machine the specified face only.
Gerber Edge.Cuts describes THROUGH routing. Pocket contours are annotated
on Dwgs.User; depths are in the tables and 3D STEP. Do not route them through.

For a whole case quote six designs, base/lid countersinks, eight B-side
pockets and one F-side shoulder seat. Confirm milling/fixturing, thickness,
profile tolerances and finish with the supplier before production. Preserve
the closed retention slots and visible edges. Build a fit sample first.
No factory order or physical qualification is implied. See PORT-DESIGN.txt.

References:
https://jlcpcb.com/help/article/countersink-hole-process
https://jlcpcb.com/capabilities/pcb-
https://learn.adafruit.com/colorful-creations-with-the-new-jlcpcb-pcb-service/advanced-adding-copper-details-to-your-design