# Original Build guide

[looking for tc36k's build guide?](../tc36k/BUILD_GUIDE.md)

# Parts List
| Part | Quantity | Details | Source |
|------------------|----------|-----------------|--------|
| M2x2x3 Insert nut | 4 | M2 thread, 2mm length, 3.0mm outer diameter | |
| M2x6x3 Insert nut | 4 | M2 thread, 6mm length, 3.0mm outer diameter | |
| M2x6 Countersunk screw | 4 | 6mm length | |
| M2x8 Countersunk screw | 4 | 8mm length (or 6mm × 8) | |
| Feet bumpons | 6 | 8mm diameter, any height. | |
| 1n4148 diode | 36 |  | [Aliexpress](https://a.aliexpress.com/_oCcCwmR) |
| Kailh Choc PG1350 HotSwap Sockets | 36 | | |
| Kailh Choc switches | 36 | PG1350 | *BUT* |
| Keycap | 36 | MBK, CFX, ... | |
| Gamma Omega PCB | 2 | 1.6mm thickness | JLCPCB |
| Top case | 1 | SLA Resin | JLC3DP |
| Bottom case | 1 | SLA Resin | JLC3DP |
| Pi Pico USB-C RP2040 | 1 | YD-RP2040 Variants are tested. [Info](https://circuitpython.org/board/vcc_gnd_yd_rp2040/) | [Aliexpress](https://a.aliexpress.com/_opuRQZl) |

> [!NOTE]
> This *requires* a variant of the original Pi Pico design with 28 GPIOs available (GP29 and GP23 on pins 35 and 37).
> The bottom case has a hole allowing access to the boot button on the RP2040 controller, which is mounted facing down once fully assembled.
> The placement of any boot/reset/user buttons varies between boards, even if they are pin-compatible.
> The expected placement (looking at the controller chips upward with the USB and pin 1 at the top) is on the left near pins 7, 8 & 9 (GP5, GND & GP6).
> This is the "black" controller at the Ali Express link:
> ![YD_PR2040 "black" Pi Pico microcontroller](../images/black-raspberry-pi-pico-boot.png)

> [!TIP]
> Actually, the PCB is compatible with choc v2 and Lofree POM switches.
> However, since the key spacing is 18x17mm, there may be issues with keycap compatibility.
> Consider the Tai Hao "THCS" or square "MT 165" with the cross stem option.


## Tools

- Soldering tools.
- Safety gears.
- epoxy adhesive
    - or cyanoacrylate adhesive would be fine too for fixing inserts.

> [!WARNING]
> For your safety: Wear protective eyewear, be cautious of hot components, and ensure proper ventilation to avoid inhaling toxic fumes.

# Build Guide


## Firmware Flashing
1. Press and hold the `BOOT` button while connecting the controller to your computer by USB.
2. Release the `BOOT` button when a Mass Storage device named "RPI-RP2" appears.
3. Copy the `gamma_omega_vial.uf2` firmware file to this storage device.
4. The storage will disconnect automatically, and the device will function as a keyboard when the firmware is successfully installed.
5. Disconnect the USB cable.

> [!TIP]
> Flashing *before* soldering in the PCB should catch a bad controller early on.


## Diodes Installation
![Diode](../images/bg.jpg)
> [!IMPORTANT]
> Install diodes with their direction matching the PCB silkscreen markings

![diode2](../images/bg-1.jpg)
![diode3](../images/bg-2.jpg)

1. Install diodes carefully, paying close attention to the correct orientation.
2. The direction of the diode must match the silkscreen markings on the PCB.
3. Ensure all diodes are mounted flat against the PCB and aligned straight between the holes.

## Hotswap Socket Installation
![hotswap](../images/bg-3.jpg)

1. Install hotswap sockets according to the PCB markings.
2. Ensure correct orientation of the sockets; while they can physically fit in either direction, the bottom case cutouts are designed for the correct orientation only.

## Pi Pico Installation
![pico](../images/bg-4.jpg)

1. Install the Pi Pico on the UP side of the PCB (opposite from where sockets and diodes are installed).
2. Position the Pi Pico with its components facing down toward the PCB and the USB port facing outward.
3. Use two 2.54mm × 19-pin headers (typically with ~2.5mm height insulators) to solder the Pi Pico onto the PCB.

> [!NOTE]
> Do not solder the top left and right pins (the ones closest to the USB port).

> [!WARNING]
> Once soldered, the two PCBs are held together by only a few points. Please be careful when handling them, as they can be easily damaged before being placed in the case

4. After soldering, carefully trim all protruding pins with a nipper.

> [!CAUTION]
> For your safety, please wear safety glasses — trimmed pins can be sharp and may fly off during cutting.


![final-pcb](../images/bg-5.jpg)
*Your PCB should look like this when completed*


## Testing
Use your favorite keystroke tester (or Vial's Key matrix tester) with a conductive tweezer to verify that all keys are working properly.


## Case Assembly
![topcase](../images/bg-6.jpg)

1. Install 6mm threaded inserts with epoxy adhesive on the top case (upper side, near the USB port hole).
2. Install 2mm threaded inserts with epoxy adhesive on the top case (lower side, opposite the USB port hole).

![put-pcb](../images/gamma2.jpg)

3. Place the PCB onto the top case.
4. Install switches into the top case while holding the PCB (hotswap sockets) in place.
5. Place the bottom case onto the top case assembly.
6. Secure with screws (8mm or 6mm for upper side, 6mm for lower side).

> [!CAUTION]
> Do not over-tighten: the screws only need to support the bottom case's weight.

7. Apply the six feet bumpon stickers to the sunken circles on the case bottom.

## DONE!
![back](../images/gamma1.jpg)
![front](../images/gamma_7.jpg)

### Everything is done.

how does it feel? Comfortable? Any issues? Does it work as you expected?

Whatever the result, I’d really appreciate it if you shared your experience with the community.


Thank you for building it!