Flat camera window
Cut a Ø22±0.2mm disk from RS PRO7698720 clear1mm polycarbonate sheet. Preserve its factory optical faces. Receive sheet thickness0.9–1.1mm and reject scratched, hazy or warped optical areas. Thickness limits are engineering receiving requirements; the source specifies nominal1mm.
Die-cut 3M VHB LSE-060WF0.6mm tape toØ22 outside/Ø17 inside, each±0.2mm. Its manufacturer thickness tolerance is±15%. Register the disk/ring on theØ24mm flat PA12 bond land within0.3mm radial offset. The window projects1.6mm beyond the original case front nominally, making assembled length105.6mm. The worst projection within the stated axial tolerances is2.09mm.
Depowder and fully dry the MJF PA12. Check the land against a straightedge and lightly lap if required to obtain≤0.20mm flatness; keep the land datum within±0.30mm. Remove dust and clean as directed by3M. Apply two thin coats of3M Primer94 to the porous PA12land, allowing each to dry fully, typically5minutes. Keep primer away from optical PCfaces. A continuous, uniform primed surface is required; a coupon made with the actual printed finish verifies adhesion and sealing before first-article assembly.
Apply the tape and window at21–38°C with at least100kPa pressure over the annulus (approximately15.3N distributed force). Use a flat annular fixture around the clear optical region; maintain registration. Allow72hours at room temperature before the final seal test. The1mm sheet provides compliance; the thin tape and specified flatness must be qualified together on the actual PA12surface.
The generator checks a conservative circular120° viewingcone from the full5.96mm lens face. The tolerance calculation includes camera depth±0.20mm, land axial±0.30mm, tape±15%, PCthickness±0.10mm, disk/ring diameter±0.20mm, registration±0.30mm and aperture diameter±0.30mm. Minimum remaining radial margins: gasket0.487mm, PCedge1.082mm, tunnel0.184mm. Source files and evidence hashes are in sources/flat-window-source-evidence.json; measurements and calculations are exported in clearance-report.json.