This is a smallKeyboard build guide. I hope it helps. Please let me know what is missing.
Prerequisites
Why Build a Keyboard
Keyboards come in different sizes. When you talk about keyboard sizes you talk about the number of keys. Most normal consumer keyboards are 104% (104 keys, it is common to add the %). Choosing another uncommon Keyboard size and customizing it to your needs can be great.
Please read Introduction to Small Keyboards - Keeb Supply Docs if you are interested to try small keyboards.
Database keyboards
Split keyboard database GitHub - diimdeep/awesome-split-keyboards: A collection of ergonomic split keyboards ⌨
Switches
Cherry Stem
There are a few switch types out there in the market. On Mechanical Keyboard Switches Chart you can look at the different switch types. The cherry stem based keyboards spacing is 19mm in both dimensions.
Choc low profile
I really enjoy low profile Choc v1 switches because of their size. Personally I enjoy 15g to 20g actuation force, so very light springs for my choc switches. This is preference and only by trying you find out what switch suits your needs. The choc spacing is 18mm times 17mm. Choc switches can be mounted on cherry stem keyboards is the compatible mounting holes are used. Here we will have a visible gap getween all the keycaps.
Keycaps
Read more about Keycaps here: Keycap Profiles: The Ultimate Guide - TEKSBIT. Because I really like the Choc v1 switches I have to get Low Profile keyswitches.
Kailh low profile switches
I don’t like them but they’re very cheap.
MBK
Great allrounder and also not so expensive. Check them out on MBK Keycaps.
Asymplex CS
These keycaps are handmade and have a luxurious feel and look. They are very pricey and come form theUSA (impot taxes might apply).
They come in a few colors.
They also come in artisan styles:
Artisans are around $250.
Everything can be bought at Choc | Asymplex.
PCB
There are two options to buy a PCB. Retail shop and order from a pcb manufacture. You could always handwire your keyboard.
Retail shop
The PCB can be bought from retail shops like broadsource, keen.io beekeeb.com and splitkb.com and many more.
PCB manufacture
It might be cheaper to buy the PCBs from a PCB manufacture. The drawbacks are that you can only order a PCB if you have the productions files. The minimum order quantity is 5 pcs. Designing your own keyboard is easy and fun. Check out my Unibodysweep V2.
Shipping gets expensive for bigger PCBs. Expect to pay €30 for a small unibody pcb and more for bigger ones.
Look and aesthetic
PCBs come in different colors with little to no mark up fee depending on the configuration.
Customizing your silkscreen is recommended and interesting. I’ve experimented with Pop-Art and different fillings to achieve certain looks. Simplicity is key.
Case
Technically you don’t really need a case for a keyboard. I don’t use any case for my Ferris sweeps. A case has it’s benefits and protects from
- dust and dirt
- ESD (electrostatic discharge)
- physical deformation through drops
- liquids With a case the keyboard is made into a nice rounded element that doesn’t have weird keypins protruding.
If you have a case that is not transparent the Look and aesthetic of the PCB is not so important.
The case is even more of a aesthetic choice than the PCB.
Hollow cases made out of light material are inherently good at transmitting sound. There are a lot of solutions to dampen the sounds that get produced by the case while typing on its installed keyboard.
There are different mounting solutions to mount the PCB to the case. There are solutions that include foam or other vibration absorbing material. My solution for my Unibodysweep V2 was to just build a small bumper. It is not a common case type but it doesn’t have any auditory problems.
MCU
Bluetooth
A very interesting and extensive resource I’ve used is Jorics guide. Because of his design I could bring my logo onto the back of a self soldered and programmed nrfmicro.
NRF 52840
There are a lot of options with this soc.
- Nice!nano
- Supermini nrf52840
- nrfmicro by joric My recommendation would be to buy the supermini. It needs a small adjustment pointed out by joric and others in order to be power efficient.
Battery
Again Jorics guide might be useful. I just use 70mAh lipo batteries. You can find them for cheap on AliExpress and similar shops.
Building
Hardware
Before you actually build the hardware you should take a look at Different keyboards and their layouts.
Soldering
There are a lot of guides on the internet. I would beginners recommend to buy solder paste and a hot air station instead of a soldering iron and solder tin. It is easy in comparison. The melting point is lower.
Software
Before you actually build the software you should take a look at your Keymap.
ZMK
I really like zmk. The docs of ZMK an be found here: Introduction to ZMK | ZMK Firmware. This firmware is designed mainly for Bluetooth keyboards in mind.
QMK
QMK Firmware Most well known keyboard firmware. I had been using it for several years before I changed to ZMK. I would recommend it over ZMK if you go for a wired only build.
KMK
KMKfw | KMK Has a lot of features ZMK dose not have. Runs on python and has a higher battery consumption compared to ZMK.
Keymap
My Keymap is public. You are free to tinker with your keymap and make changes on the go. Starting with QWERTY or the keymap you are already familiar with is a wise choice. You might just make a few changes and try it out. In ergo circles, it is usually recommended that you stay on qwerty for rowstagger boards and then use good keymaps for colstagger. This way you keep two independent muscle memories that hardly interact and can continue to type on other people’s keyboards if necessary.
In my opinion there is not a perfect keymap and the keymap is always a work in progress. I believe that having 2 layers for typing is okay. More would be too confusion. I used combos for a while but the problem with combos is that your accuracy is limited. Stenographers would disagree with this statement. You can always optimize your keymap to get down to just a few keys. In my opinion the time for the fingers to travel some distance is still less then to wait and layershift to another alpha layer.
Most of the optimizations under ~34 keys are not for speed, but for comfort.
If you are interested in this keymap check out apfels kilipan · GitHub. I’ve not gone below 34 keys but I should try it. Maybe with a 30 key GitHub - rschenk/tern: 30-key hot swap keyboard based on the Hummingbird.
Learning material
KeymapDB - Database of keymaps for programmable keyboards Colemak Mod-DH KeySolve