# Local structural screening

Chosen diagnostic assumptions only. Not measured print material allowables, a fatigue model, FEA, a drop rating or proof of process-independent durability. Stress results depend on full specified section/load sharing and do not certify actual molded/printed anisotropy.

Assumptions: elastic modulus1,000MPa; provisional stress screen8MPa; additional local stress factor1.5. These are deliberately stated design assumptions, not material certificates.

| Feature | Test force N | Nominal stress MPa | With1.5 factor MPa | Elastic deflection mm |
|---|---:|---:|---:|---:|
| Broadened right PCB stop | 20.0 | 5.01 | 7.52 | 0.169 |
| PTT integrated inner seat | 5.0 | 4.81 | 7.22 | 0.049 |
| Speaker keeper | 3.0 | 3.28 | 4.92 | 0.036 |
| Battery platform above rear lead | 10.0 | 1.51 | 2.26 | 0.002 |

## Limits and practical checks

- **Broadened right PCB stop:** 20N lateral USB diagnostic load on an ideal linearly tapered rectangular cantilever. Actual cable force/contact height and printed modulus are unknown. Existing shell support may shorten the span; no strength credit for it.
- **PTT integrated inner seat:** Full narrow-seat length to its broader front root. No credit for the surrounding cradle or load sharing. Wire slot geometry is a local stress raiser; cycle test remains required.
- **Speaker keeper:** 3N local diagnostic force, short span. Upper counterbore has1.2mm remaining floor and side ligaments; screw torque is not represented by this transverse beam model.
- **Battery platform above rear lead:** 10N handling screen over a3.5mm-wide local groove. Roof dimension follows platform topZ-17.3 and reserved cable topZ-18.85. Pouch must never be a closure-load spacer.

- The keyed battery post is supported by the rear shell and uses a broad anti-rotation key. Its minimum inboard pilot ligament is1.15mm. Qualify thread creation on the coupons; no screw-stripping torque is inferred from the beam calculations.
- Speaker upper screw head clears the maximum pouch by0.35mm at nominal printed dimensions. Use the specified head envelope and shorter4mm screw; verify the physical gap.
- Wire passages preserve the original exterior with a1.5mm interior clipping limit. That geometric limit is not a printer accuracy specification.
- Four PCB pads supply an estimated3.6–8.5N at the manufacturer’s25% compression condition. The maximum-board stack reaches32.1%; closure force at that condition requires the actual foam test.
- Retained volume/PTT/play mechanism screens are included separately. End/edge presses, switch travel, creep, drop/shock, screw service life and1,000-cycle performance remain physical qualifications.