Mechanical Complete System Assembly Design Spec - thepinkmile/Enigma-NG GitHub Wiki

Complete System Assembly — Mechanical Design Specification

Status: Draft Project: Enigma-NG Author: Izzyonstage & GitHub Copilot Version: v0.3.0 Associated Hardware Revision: Rev A Last Updated: 2026-04-20

Overview

This is the top-level General Assembly document for the Enigma-NG machine. It defines the complete set of mechanical and electromechanical components that constitute the finished machine and provides the authoritative assembly sequence guidance for build and maintenance activities.

All sub-assembly details, tolerances, and part-level instructions are contained in the sub-assembly documents listed in §3. This document provides the integration view: what assembles where, in what order, and with what dependencies.

Component Index

The following table lists every component category present in the assembled machine.

Category Qty Description Sub-Assembly Document
Rotors 30 Individual rotor modules (shroud, bearings, encoder slots, ERM8 male headers) Rotor/Design_Spec.md
Stator Board 1 PCB backplane: rotor stack, JTAG hub, encryption routing, I²C expanders, servo Stator/Design_Spec.md (Electronics)
Rotor Actuation Assembly 1 Depression bar, pivot lever, actuation arm, sprung retention bar, servo motor Rotor_Actuation_Assembly/Design_Spec.md
Keyboard Assembly 1 Keyboard panel, key-switch harness, Encoder Module (KBD_ENC) Keyboard_Assembly/Design_Spec.md
Lightboard Assembly 1 Lightboard panel, indicator harness, Encoder Module (LBD_DEC) Lightboard_Assembly/Design_Spec.md
Plugboard Assembly 1 Two plugboard passes, four Encoder Modules, patch cables Plugboard_Assembly/Design_Spec.md
Reflector 1 Mandatory passive turnaround sub-assembly; reflection mapping is owned by the Stator CPLD Reflector/Design_Spec.md
Extension (optional) 0–N Extension board for multi-stack rotor configurations Extension/Design_Spec.md
Power Module 1 Standalone power supply sub-assembly (LTC3350, eFuse, INA219, supercaps) Power_Module/Design_Spec.md
Controller Board 1 CM5 carrier board (CM5 module, JDB hat, PM dock, Stator dock, Ethernet / PoE entry) Controller/Design_Spec.md (Electronics)
Main Enclosure 1 Chassis, panels, cable routing, EMI bonding, fan Main_Enclosure/Design_Spec.md
Servo Motor 1 Miuzei Metal Gearbox 90 (5V, 3-pin, PCB-mount on Stator) Rotor_Actuation_Assembly/Design_Spec.md
SERVO_HOME Switch 1 SPST NO momentary (Omron SS-01GL13), PCB-mount on Stator Stator/Design_Spec.md (Electronics)
Settings Board 1 Panel-mount configuration switch PCB (12× SPDT toggles, 12× discrete RGB indicators, + CFG_APPLY button); mounts to right side top face of Main Enclosure; connects to Stator via I²C ribbon Settings_Board/Design_Spec.md (Electronics)
Cable Harnesses TBD Encoder IDC ribbons, reflector cable, fan cable, Settings Board I²C ribbon, switch / battery harnesses Each sub-assembly doc
Connectors TBD TE PM dock, Molex Stator dock, ERF8/ERM8 rotor-family BtB, JST PH servo, JST SH fan, Molex IDC encoder, etc. Per sub-assembly BOM

Assembly Sequence Overview

The following is the recommended assembly order for a complete machine build. Sub-assembly build steps are detailed in each referenced document; this section defines integration dependencies only.

Step Sub-Assembly Notes
1 Power Module Standalone build; test on bench before integration. Delivers 5V_MAIN and 3V3_ENIG.
2 Stator Board Install ICs (CPLD, MCP23017 ×3, PCA9685, INA219), passives, connectors. Mount servo + SERVO_HOME switch. Bench-test I²C expanders before stack assembly.
3 Rotors (×30) Build all 30 rotor modules. Verify ERM8 header alignment and encoder slot clearance before stacking.
4 Rotor groups onto Stator Press Rotor 1 ERM8 headers into Stator ERF8 sockets. Build the first 5-rotor group, then insert an Extension before each further 5-rotor group as required. Verify JTAG daisy-chain continuity at each group boundary.
5 Rotor Actuation Assembly Install depression bar, pivot lever, actuation arm, sprung retention bar. Connect servo 3-pin JST to Stator J_SERVO. Verify SERVO_HOME switch actuation.
6 Keyboard Assembly Build keyboard panel + KBD_ENC Encoder Module. Connect IDC ribbon to the Stator keyboard encoder port.
7 Lightboard Assembly Build lightboard panel + LBD_DEC Encoder Module. Connect IDC ribbon to the Stator lightboard decoder port.
8 Plugboard Assembly Build both plugboard passes. Connect IDC ribbons to the four Stator plugboard ports (PLG_PASS1_DEC, PLG_PASS1_ENC, PLG_PASS2_DEC, PLG_PASS2_ENC).
9 Reflector Install the mandatory passive Reflector sub-assembly at the far end of the final rotor group. Connect the 16-pin cable to Stator J10. Reflection-map selection remains Stator-CPLD-owned.
10 Extension (if used) Insert each Extension between 5-rotor groups: Stator -> 5 rotors -> [Extension -> 5 rotors]* -> Reflector. Each Extension reinjects clean 3V3_ENIG/GND to the next rotor group via J7 -> J5.
11 Controller Board + JDB Hat Install JDB hat on Controller. Mount Controller in Main Enclosure. Engage the TE PM dock cluster (J1/J2/J3) to the Power Module, then mate the Molex Stator dock pair (J4/J5J11/J12).
12 Settings Board Mount Settings Board PCB to Main Enclosure right side top panel. Route the 6-wire harness (3V3_ENIG, 5V_MAIN, GND, SDA, SCL, GND) to Stator J_CFG. Verify U_EXP_SW_IN, U_LED_B1, and U_LED_B2 appear on the shared I²C bus, then run a functional check that reads switch-state changes and drives each bank's RGB indicator rails before final panel closure.
13 Main Enclosure final assembly Route all cable harnesses. Install panels. Fit fan. Secure EMI bonding. Final torque fasteners.

Note on the JTAG Daughterboard (JDB): The JDB is a PCB hat that mounts directly on the Controller Board. It has no independent mechanical assembly step — it is installed as part of Step 10 (Controller Board install) before the Controller is fitted in the Main Enclosure. See design/Electronics/JTAG_Daughterboard/Design_Spec.md for electrical details.

Sub-Assembly Reference Table

Sub-Assembly Document Status
Main Enclosure Main_Enclosure/Design_Spec.md Draft
Rotor Actuation Assembly Rotor_Actuation_Assembly/Design_Spec.md Draft
Rotor Rotor/Design_Spec.md Draft
Keyboard Assembly Keyboard_Assembly/Design_Spec.md Draft
Lightboard Assembly Lightboard_Assembly/Design_Spec.md Draft
Plugboard Assembly Plugboard_Assembly/Design_Spec.md Draft
Power Module Power_Module/Design_Spec.md Draft
Extension Extension/Design_Spec.md Draft
Reflector Reflector/Design_Spec.md Draft
Settings Board design/Electronics/Settings_Board/Design_Spec.md Draft

Cross-References

Document Description
design/Electronics/Settings_Board/Design_Spec.md Settings Board electrical specification — panel switches, LED expanders, I²C interface
design/Electronics/Stator/Design_Spec.md Stator Board electrical specification — J_CFG I²C connector to Settings Board
design/Mechanical/Main_Enclosure/Design_Spec.md Main Enclosure — Settings Board panel cutout requirements
design/Guides/Maintenance_Guide.md Maintenance procedures referencing assembly steps
design/Guides/User_Manual.md User-facing assembly and operation guide