I designed another weird keyboard

The original egg58 prototype used Choc V2 switches, which have MX-style stems and therefore support a wide selection of keycaps. However, it turned out that DSA, the shortest keycap profile widely available, would still bottom out if the switches were plate-mounted. The egg58 layout was not really conducive to PCB mounting, so I switched to original Choc switches.

This left me with a supply of Choc V2 switches and DSA caps which have gone unused for over a year now. I thought the egg58 was my endgame. It probably still is, but nonetheless I have made another keyboard. Just to put those spare parts to use.

I decided early on to go with an ortholinear layout, approximately 60% but arranged similarly to the egg58. At some point, I started considering adding a trackpoint to the board, like what they have on ThinkPads. It turned out that the availability of trackpoint modules isn’t too great, and there’s difficult to integrate, so I settled for a small joystick instead.

I stuck the joystick right in the middle of the keyboard, added two additional keys for left and right click, and landed on a semi-split design.

After a few hours in KiCad, I ended up with this.

pcb layout

The only difficult part was figuring out a solution for the 2u positions. As you can see here, there are three switch positions for the 2u keys. I found that some of my 2u keycaps had the stem in the middle, while others had two stems placed 1u apart. Therefore, I needed the provide the option to populate switches to support either.

I wanted to target using a Pro Micro for the MCU, since I had a bunch of spares of those lying around too. It turns out that it has just enough pins to support a 10x6 matrix and two ADC channels for the joystick. There is no wasted I/O on this board.

The next step was to order the prototypes. PCBWay kindly reached out to sponsor PCB prototyping for this project. Their ordering process was straightforward, with a lot of options available. Notably, they offer a matte black solder mask, which was not available from my previous PCB supplier. Having seen it on other peoples’ projects, I knew it would look great for this keyboard.

Unfortunately, right after submitting my order, I noticed some errors in the design. I missed copying some of the mounting holes when altering the footprint for those weird 2u positions. Fortunately, once I fixed it, their support team was able to quickly replace the Gerber files before the boards went to production.

It only took a week for the boards to arrive. The matte black finish looks great, and there is a noticible improvement in the quality of details compared to the PCB producer I used previously. The cuts are smoother than I’m used to, and the silkscreen resolution seems higher.

bare PCBs

I also got an SMT stencil from PCBWay, which made it incredibly easy to assemble the board.

assembled PCBs

After adding switches, keycaps, and a 3D printed case, the tamago60 is complete.

final assembled board

Of course, the design is open source. I’ve also shared the project on PCBWay so you can easily order your own board: