abse/museair-usb

mechanical/light-pipe/VLP-350-F.md

# Flat Bivar VLP-350-F assembly proposal

Purchased part: https://www.digikey.com/en/products/detail/bivar-inc/VLP-350-F/2407219
Drawing: https://www.bivar.com/parts_content/Datasheets/VLP-XXX-X.pdf revision L.

Drawing-based CAD reconstruction, not OEM CAD. Clear polycarbonate, flat 2.9972 mm face, body height 8.89 mm. Base envelope 4.699 mm square, 2.667 mm deep; recess 3.556 mm square and 2.159 mm deep. Transition profile is undimensioned and illustrative.

PCB surface Z38.6; lid Z45–47. Lens face Z47.49, 0.49 mm nominal projection. D1 model top Z39.41; cavity roof Z40.759 gives 1.349 mm optical clearance. The lid opening is 3.0734 mm, a nominal diametral clearance of 0.0762 mm. Supplier general dimensional tolerance and printed lid accuracy still require a physical sample fit; this is not a guaranteed clearance.

Two mounting pins are 0.5842 mm diameter, 1.524 mm long. Manufacturer nominal drills 0.6096 mm, range 0.5588–0.6858 mm, at world XY (-9.7728,20.532) and (-13.2272,16.468), after rotating the square part 90 degrees about the LED. The main index PCB now contains both non-plated 0.6096 mm mounting holes, with 0.30 mm copper clearance on both layers. The main board was rebuilt with the new holes. Two bottom speaker tracks were detoured around the right-hand hole, preserving terminals, 0.20 mm widths and vias. Ground pours were refilled. All 244 source pin/net assignments, component positions and imported pads are unchanged. Circuit routing checks, Gerber shorts scan and native KiCad DRC pass with zero errors and zero unconnected copper. CAD collision diagnostics include nonphysical top texture planes and the intended PCB seating contact; native drill and copper-clearance checks verify the actual geometry.

The pipe stays with the PCB when the lid is removed. Its independent CAD group can be hidden separately. The section and mounting-detail renders tint the clear part for visibility. Main index source, assembly real board model and local drill/Gerber/BOM/CPL outputs were regenerated. Publication status is recorded separately in validation/lightpipe-publication.json.

Generate with PYTHONPATH=/workspace/museair-assembly/python python scripts/add-flat-light-pipe.py, build assembly with tsci build assembly.circuit.tsx --disable-parts-engine, and render with viewer/render-flat.mjs. Existing full enclosure generator dependencies are not restored in this isolated review directory.

The reproducible main build uses `npm run build`: tscircuit generates source/footprint/placement artifacts with initial automatic routing disabled, then the existing postbuild runs guarded reviewed-copper replay and the two local detours, refills pours and runs all circuit checks. This preserves the audited board rather than replacing unrelated routes. The replay guard validates exact pads/nets and both new drill/clearance dimensions. Native KiCad DRC and Gerber shorts checks additionally validate the completed copper.