The project documents confirm the full enclosure can proceed as a preliminary modular concept, but the heater block, OLED, encoder, and optics have not yet been dimensioned. I’ll design those as replaceable modules with clearly marked provisional envelopes, so the external arrangement can be approved without pretending the final tube fit is verified.
I’ve fixed the preliminary architecture: a 148 × 138 mm benchtop shell, the live 100 × 100 mm PCB low in the base, a separate rear opaque chamber, and a sloped front OLED/encoder panel. The tube envelope is based on published 0.2 mL PCR-tube dimensions; all heater, optical, and UI mounting details remain explicitly provisional until parts are selected.
Concept revision: v1 — awaiting visual approval. This is geometry-bound preliminary massing, not printable release CAD.
The native enclosure-concept inspection could resolve the board outline and connectors but found no usable component 3D bodies. The review assembly therefore uses a deterministic PCB proxy based on the live 100 × 100 mm outline, four measured mounting holes, and connector footprint envelopes. The PCB is not recentered or resized.
The concept is 148 × 138 × 92 mm, with a translucent PETG shell, sloped OLED/encoder panel, current PCB geometry, and separate black optical/heater chamber. Exact heater, optics, and UI mounts remain provisional; details are recorded in Enclosure Concept Design Record.
Please approve this visual direction or provide text/marked-up-image changes. Once approved, I’ll create the detailed printable base, lid, chamber, mounts, openings, and hardware.
This review checks the routed 100 × 100 mm board against connector mating access and M3 mounting hardware. It uses the live PCB coordinates, footprint/model read-back, rendered board geometry, datasheet dimensions, and conservative hardware envelopes.
Overall status: PASS WITH CONDITIONS. No PCB placement change is currently required. Enclosure release remains blocked until the connector openings, removable-lid strategy, cable bend space, and exact fastener stack are incorporated into the enclosure CAD.
Assembled board 3D view
Connector inventory and mating directions
Table
Interfaces
Type
Mating direction
Finding
J1, J2
KF128 5.08 mm screw terminal
Wire enters horizontally through the board-edge face; screw access is from above
Edge placement and outward-facing openings are correct. Enclosure needs aligned side openings, straight wire-entry volume, and top screwdriver access. Exact body/access dimensions remain drawing-derived and should be checked against the purchased vendor lot.
J3–J10
JST XH top-entry headers
Vertical, normal to PCB (+Z)
All headers have usable vertical mating access on the bare board. A fixed close-fitting lid would block assembly/service.
U1 USB
Raspberry Pi Pico Micro-USB
Horizontal through the lower board edge
Connector is positioned at the carrier edge and needs a panel opening plus external plug/strain-relief volume. Pico is 51 × 21 mm and its USB connector overhangs its board edge.
The XH series specifies top-entry headers and an assembled board height of 9.8 mm. The 5-position header is also identified as top-entry; its matching XHP-5 housing is 14.8 mm along the circuit row.
JST housing-to-housing clearances
The following gaps use the placed center spacing and matching XHP housing row lengths. They check rigid housing interference, not finger access or wire bend radius.
Table
Pair
Center spacing
Housing-envelope gap
Result
J3–J4
12.0 mm
about 4.7 mm
Pass
J5–J6
9.0 mm
about 1.7 mm
Pass, tight service access
J7–J8
18.5 mm
about 2.45 mm
Pass, tight service access
J9–J10
17.0 mm
about 4.7 mm
Pass
The 2-circuit XHP-2 housing is 7.3 mm along the row. The 4-circuit XHP-4 housing is 12.3 mm along the row. J8/XHP-6 dimensions were not fully machine-verified from the attached J8 source; this review uses the JST XH family drawing and the actual J8 3D model as nominal geometry.
Required enclosure allowance
Keep the region above J3–J10 open during mating and service.
Provide at least 25 mm clear height above the PCB over the JST banks as a provisional housing-plus-wire-bend envelope; 30 mm is preferred where the harness turns immediately.
Use a removable lid or connector access hatch. Do not trap these top-entry housings beneath a non-removable close lid.
Because J5/J6 and J7/J8 are closely spaced, do not place enclosure ribs between each pair unless the harness CAD proves insertion and latch access.
M3 mounting-hole validation
Hole geometry
Hole1–Hole4 are Ø3.4 mm NPTH at (±44, ±44) mm.
Each center is 6.0 mm from the two adjacent 100 mm board edges.
Ø3.4 mm is a normal-clearance M3 hole.
Hardware envelopes used
Table
Hardware
Conservative envelope
M3 socket-head screw
Ø5.5 × 3.0 mm head
M3 DIN 125 washer
Ø7.0 × 0.5 mm
M3 hex nut / common hex standoff
5.5 mm across flats; up to about 6.35 mm across corners
A Ø7 mm washer leaves 2.5 mm of board material between the washer edge and each adjacent board edge. The four 14 × 14 mm corner inspections found no routed copper or unrelated component body in the hardware zones.
Tightest corner: Hole4 near J8
The J8 STEP/GLB model was measured directly. After applying its PCB rotation and position, the nearest J8 plastic-body end is approximately 5.05 mm from Hole4 center. This gives:
about 2.30 mm clearance to a Ø5.5 mm screw head;
about 1.55 mm clearance to a Ø7.0 mm washer.
Result: pass, but do not use an oversized washer, boss, or standoff envelope larger than Ø7 mm at Hole4 without rechecking. The 2D footprint envelope appears to overlap the hole area because it includes pads/silkscreen; the measured plastic body does not collide.
J8 and Hole4 close-up
Underside and standoff recommendation
Use 8–10 mm M3 standoffs for the first enclosure revision.
Trim through-hole leads to no more than 2 mm below the PCB after soldering.
Keep enclosure bosses and metal hardware within a Ø6.5–7.0 mm corner envelope.
If conductive metal standoffs are used, retain the present NPTH/no-copper corner zones and add an insulating washer if production hardware varies.
Terminal-block and USB panel requirements
J1 and J2
Openings must align with the horizontal wire-entry faces.
Reserve at least 15 mm straight external access in front of each opening for insertion and initial wire bend; increase this after the actual wire gauge and ferrule are selected.
Preserve vertical screwdriver access above both blocks.
The terminal datasheet specifies a 6–7 mm wire strip length.
U1 Micro-USB
Provide a lower-edge panel cutout centered on the Pico USB connector.
Use the actual selected Micro-USB cable plug for final cutout validation; plug shells and strain-relief boots vary and the Pico datasheet does not publish a universal cable-clearance envelope.
Start enclosure CAD with a provisional 12 × 7 mm opening and at least 15 mm external plug/boot volume, then tune against the chosen cable.
Remaining mechanical release gates
Select the actual J1/J2 wire gauge, ferrules, and cable exit directions.
Select the actual JST harnesses and establish immediate wire bend directions.
Select screw length, standoff height, washer usage, and enclosure boss diameter.
Add simplified mating plugs, cable cylinders/bend envelopes, and fastener solids to the enclosure assembly.
Run interference checks in both assembled and service/removal positions.
Print a corner-and-connector fit coupon or an enclosure base prototype before manufacturing release.
Acceptance criteria for enclosure CAD
No solid interference in assembled position.
At least 0.5 mm nominal rigid-plastic clearance; 1.0 mm preferred around removable connectors.
J1/J2 wire entry and screwdriver axes remain unobstructed.
JST housings can be inserted and removed with the lid/access hatch open.
USB plug can be inserted without levering against the PCB or enclosure.
No screw head, washer, standoff, nut, or boss exceeds the validated Hole4/J8 envelope.
Bottom lead tails maintain at least 3 mm clearance to the enclosure floor or any conductive feature.