# Walkie One 28.1 / R3.6 — Changes explained

## Same exterior. Stronger internals.

This is Walkie One twenty-eight point one, revision three point six. We went back to the original revision three point four and kept the bare case at seventy-eight by one hundred fifty by twenty-four millimeters. The outside shape, bumper, visible buttons, openings, grille and seam are preserved. The changes are inside.

## Review the whole assembly

The battery compartment and volume-button legs showed where the first build struggled. The review extended to every original printed component, plus fasteners, electronics supports, wires and soft pads. The design approach is to shorten unsupported spans, broaden fragile roots, and make parts removable without bending thin printed catches.

## A battery that can drop into place

The battery space uses the agreed maximum battery body, plus assembly clearance. Low, rounded locating supports and removable bridges replace the restrictive fence arrangement. The battery goes in with the bridges removed. The screws seat against supported structure, while the pouch remains free of clamping pressure. Defined pad thicknesses and lead channels control the remaining space. The actual wrapped battery and factory lead still need measuring.

## Broad sliders replace fragile legs

The volume buttons keep their original visible caps. Inside, the narrow legs become broad sliders with wider capture flanges and blended roots. Each slider enters an open guide before its separate keeper is screwed down. That avoids flexing a fragile retention feature during assembly. Supported stops limit movement. Real switch travel and return still need checking.

## Support every control

The push-to-talk carrier loses its long projecting printed rods. Broad captured sliders, end guides and a central stop support it instead. The play button gets larger capture bars and stops supported directly by the shell. Switch-cradle roofs are also thicker. These changes aim to spread off-centre pressing loads through stronger sections. The visible button shapes stay the same.

## Give the screws solid material

The speaker keepers originally had about a quarter millimeter of material beside their countersinks. The revised keepers provide one point five millimeters there. Microphone and light retainers gain broader screw seats. Shell bosses and other support roots receive local backing. Head size, engagement and blind-hole depth are coordinated, so every specified screw has a defined seat and tip margin.

## Support the board. Control the wires.

All eight original circuit-board support roots are reinforced, and three new pads support additional board edges without moving the electronics. Compact antenna clamps replace fragile frame details. Defined cable routes and replaceable strain restraints keep wires away from moving controls. Pads, films and adhesive are treated as an installed stack. Doubling a layer could consume the available clearance.

## Keep the factory battery lead intact

The battery keeps its factory plug, protection, tape and leads. A small removable adapter provides the connection within the fixed enclosure. Its carrier, insulation and cover have defined support and screw access. The assembly order matters: thread the loose cover onto the adapter wires before soldering, then install the completed module before the main circuit board.

## Assembly order is part of the fix

Fasten the antenna clamps before installing the battery. Fit the volume keepers before dressing the nearby common wire. Tighten the battery keepers before routing the adjacent factory lead. Keep the bumper off during fastening, and fit it last. Both case halves must seat fully by hand. If they need screw force to close, stop and find the interference.

## What the CAD checks establish

The final checks cover exterior preservation, complete assembly clearances, fastener heads, tool access and control movement. All four controls passed the nominal movement checks, including selected rocking positions and simultaneous presses. The native Fusion archives reopen, and the twenty-eight print meshes are valid and closed. The risk register records each concern, its treatment and its remaining test.

## Why we expect better durability

The expected improvement comes from broader load-bearing sections, shorter spans, supported screw seats and assembly that does not require bending fragile parts. That is a stronger mechanical rationale, but physical durability has not yet been demonstrated. Qualify the coupons for each printing process, measure the actual battery and switches, then complete ten service cycles and a thousand presses of each control. Inspect for cracks, binding, loosening and cable pinching, and check electrical and radio performance. The exterior stays fixed throughout that qualification.