# R3.2 A — assembly and test notes

Prototype candidate, 2026-09-11. Use with the complete R3.2 A reference assembly and README. These instructions supplement the frozen R3.1 package; they do not release this candidate for production.

## Changed parts and supplies

| Part | Qty | Material / role |
|---|---:|---|
| Front shell with split PTT guides | 1 | Inherited rigid shell material intent; PLA only for preliminary fit printing |
| Rear shell with coax saddles | 1 | Inherited rigid dielectric shell material intent |
| PTT carrier with twin integral guide pins | 1 | Rigid carrier; same orange outer grip remains separate and unchanged |
| Lower LTE frame with cable bridge | 1 | Rigid dielectric frame; no metal substitute near the antenna |
| PTT guide cap 1, lower | 1 | Rigid, removable; fit bore and registration details to its front-shell half |
| PTT guide cap 2, upper | 1 | Rigid, removable; not interchangeable with cap 1 |
| M2 × 5 pan-head guide fixing | 2 additional | Nominal reference: 3.5 mm head diameter, 1.3 mm head height. Actual screw/retention process to confirm |
| Dielectric retaining tape | 2 installation positions | Modeled envelope 5 × 6 × 0.08 mm each; grade and adhesive to select and test |
| Taoglas FXUB63.07.0150C antenna/coax/plug | 1 existing selected part | The antenna, lead and plug are one purchased assembly; do not fabricate the CAD cable/plug proxies |

Inherited shell, cap, rim and grip finishes/colour intent remain unchanged. Guide bores and sliding pins need controlled finish and fit; do not add cosmetic coatings to those interfaces before checking clearance. Existing material intent does not specify or qualify a final casting resin.

## PTT assembly

1. Remove both new guide caps. Fit the original switch cassette/contact and keep the inherited matched stop arrangement; do not randomly change shims to compensate for an unmeasured switch.
2. Insert the revised PTT carrier from the rear so both integral pins lie in the open front guide halves. The caps must be removable; do not glue them to the carrier.
3. Check for burrs, print ridges and support residue. The nominal 0.1 mm radial running clearance is a CAD target, not a guarantee from a 0.4 mm nozzle. Measure and finish the bores/pins as a matched set. The small registration details may need higher-resolution fabrication or careful finishing.
4. Fit cap 1 at the lower station and cap 2 at the upper station. Seat registration details without force. Fit one M2 × 5 fixing per cap, before installing the PCB over this region. Do not force a metal machine screw into an unprepared brittle printed/cast pilot. Have RPS specify the pilot/tap or appropriate resin-compatible fastening process and torque.
5. With actual switches installed and wired, check center, upper-end and lower-end actuation and full return. Repeat with the rear cover fastened and all wires dressed. Stop and investigate any catch, persistent preload, loss of electrical release or visible pin/cap flex.

The 0.45 mm stroke and 0.15 mm released gap are inherited nominal values. The actual LIDUOLE assortment switch tolerances, free/operating height, terminal envelope, travel and force are not verified. Do not close the PTT review issue based only on an empty-case print or the CAD tilt plots.

## Antenna and cable assembly

1. Confirm the received antenna against the [Taoglas datasheet](https://www.taoglas.com/datasheets/FXUB63.07.0150C.pdf), especially its feed bond, 150 ±9 mm lead and connector. The modeled feed/plug are installation assumptions derived from the drawing and PCB model, not a corrected supplier STEP.
2. Install the antenna on the inherited dielectric seat. Keep its active flex flat and uncut. Do not add the omitted GNSS antenna/cable.
3. Run the coax down the illustrated long edge, through the new lower-frame relief, around the service loop and back up the two rear saddles to the cellular PCB connection. Confirm the board connection is J5 with Elian before powering. The route envelope is not permission to stretch the cable or load its antenna bond.
4. Fit the frame bridge above the cable channel. Lay the cable into the open saddles and retain it with dielectric tape on the lands. Do not squeeze the cable with the tape, put adhesive on the connector or substitute metal clips. Test tape adhesion and inspect for pinching after closing the rear cover.
5. Adjust the bottom service loop for the received lead length. Hidden 141 and 159 mm alternatives show the tested extremes. The 5 mm bends and plug envelope still need sample confirmation. Confirm sufficient service slack for the chosen assembly order; the static closed-case route does not verify opening the case while connected.
6. Inspect the actual connector engagement, all populated-board components, battery padding and dressed harness. U6 is still a nominal 24 × 24 × 2.4 mm placeholder; the corrected populated STEP and real assembly remain necessary.

## Print and evaluate

The six STL files are in millimetres and retain assembly coordinates. They are not pre-oriented/sliced P1S jobs. In Bambu Studio, place/orient each part and inspect supports, layers and bore surfaces before printing. For the known P1S 0.4 mm nozzle and PLA, use these as fit prototypes. Do not infer cast-resin sliding performance or production strength from PLA.

A useful initial screen is 100 presses distributed across the center and both ends, recording electrical make/release and return after every press. This is a chosen prototype screen, not an industry qualification standard. Inspect guide pin roots, caps and tiny registration features for damage. Check the antenna route again after assembly and handling.

This candidate can support those tests now. Manufacturing release still needs measured switches, antenna/connector installation approval, acceptable RF performance, material/fastener qualification and the other outstanding R3.1 review checks.