Klavyl is a Klavgen-based, handwired, hotswappable, split, ortholinear, 3D-printed, highly composable mechanical keyboard that has 4 rows and 7 columns, a 3-key thumb fan, is easy to solder, is low height, and has a palm rest. That's a lot, so let's decompose:

• handwired: you don't need to buy or make PCBs
• MX or Choc switches: uses either MX or Choc switches (but with MX spacing). Choc is still highly experimental.
• hotswappable: uses Kailh hotswap sockets
• split: left and right hand halves are separate
• ortholinear: keys form a line across rows, rather than staggered where each row is offset
• 3D-printed without supports on a home FDM printer, with large parts kept simple to minimize the chance of errors
• low height: only 11 mm tall, including 2mm top and bottom plates
• highly composable: small changes to the layout only require printing a top plate since the switch holders can be moved and the wrapped wires can be unwrapped to allow keys to be spaced further apart
• easy to solder: uses holders for the Kailh hotswap sockets that allow in-place soldering of the Kailh socket, diode and wires; supports bare wires without insulation, because stripping wires is a pain
• sturdy: the Kailh socket holders support the top plate to prevent bending
• 4 rows and 7 columns, plus a 3-key thumb fan: 31 keys per half, 62 total
• parametrically generated with Klavgen
• palm rests: detachable and optional

I made Klavyl as a personal modification of the excellent Redox keyboard.

The current files are meant for:

• Kailh hotswap sockets (MX or Choc)
• Pro Micro or similar boards of the same size
• USB-C connection between the two halves
• QMK for the firmware
• Printing on a reasonably tuned 3D printer. I used an Ender 3 V2.
• M3 screws with inserts that are melted into the board

If you want a different config, let me know by filing an issue.

You can find STLs in:

• /stl_mx for MX switches
• /stl_choc for Choc switches (highly experimental)

Back photo, showing the low height of 11 mm and the cable connections:

Front of 3D model, showing the top with switch holes, the bottom, the palm rest, and the USB-C jack holder:

Back of 3D model, showing the cutout for the Pro Micro:

Front of 3D model, showing all the components (top, bottom, palm rest, switch holders, Pro Micro holder, USB-C jack holder):

To see how Klavyl is built and adjust it, as well as re-generate the output .stl files (from the stl directory), check out and run the klavyl.py file.

Modify the use_choc variable to generate Choc holes and switch holders.

These are the parts you need. The Amazon links is what I used and they are non-affiliate.

You need:

• Soldering iron and everything around it: solder, safety glasses, ventilation, etc.
• Tweezers
• Wire stripper, unless you are going to strip manually or will use bare wire for the rows/columns and only use insulated wire for the Pro Micro and USB-C jacks

All the parts for 3D printing are in the stl_mx/stl_choc directories. They have been tested on an Ender 3 V2 and therefore the tolerances may not work for your printer. If that's the case, let me know by filing an issue in the project.

Below I discuss MX version, but everything is the same for the Choc versions in the stl_choc directory.

You should be able to print everything in PLA, expect the switch holders for which I recommend ABS because you'll be soldering on them and the soldering iron can very easily melt PLA.

This is what you should print:

File keyboard_bottom.stl. The bottom part, for the left hand.

File keyboard_top.stl. The top plate, for the left hand. It is flat with simple holes so that it can be made with a laser cutter or a CNC machine

File palm_rest.stl. The palm rest which attaches to the bottom via connectors. It can also be fused with the bottom, see below.

File switch_holder.stl. Holds the Kailh MX hotswap socket and allows you to solder the diode, column and row wires in-place. Print it the way it's oriented in the STL, with the flat side (that has a small hole) on the printing plate.

Note: print switch holders in ABS since you'll be soldering on them.

File controller_holder.stl. Holds the Arduino Pro Micro controller.

File usbc_jack_holder.stl. Holds the USB-C socket.

File connector.stl. Connects the bottom to the palm rest.

1. Strip wires completely for rows and columns, making sure they are about 2x the size of the plate due to wrapping. Do not leave insulated wire at the end like I did.

2. Row by row, insert the socket holders, and wrap the row wires:

Note: the 3 keys on the thumb fan are a separate row

3. Place the diodes, bending the legs on the back to hold them in place:

4. Solder the diodes and row wires, and cut the extra diode legs:

5. Wrap and solder the column wires. Note that you should not have the top and left dangling wires, as it's much better to first solder wires to the Pro Micro and then solder those wires to the rows/columns:

Note: the 3 keys on the thumb fan need to be wired to columns 5, 6, and 7 (see the picture).

6. Wire the USB-C jack to the Pro Micro. The actual wiring doesn't matter as long as it's consistent on both halves. I use the following:

   • VCC pad to VCC
   • D+ pad to 3/PD0
   • D- pad to 2/PD1
   • G pad to GND

7. Solder USB-C jack resistors ON ONE SIDE ONLY. Solder two resistors, one between the 3/PD0 and VCC wires, and one between the 2/PD1 and VCC wires. This was pretty challenging to do given the short wires and limited space. Use electrical tape to insulate the connections.

8. Solder long wires to the controller itself with the other ends dangling. See the next step for which holes on the Pro Micro to use. Don't do as in the picture above where I did the reverse and had the wires soldered to the rows/columns first.

9. Route the controller wires and solder them to the row and column wires. This is the trickiest part. Your result may look like this but it may be even better to route the wires between keys, rather than only on the top/side. Klavyl uses the same wiring as the Redox keyboard. You have to solder the columns mirrored. On both sides, column 1 is the 4-row column that is farthest away from the thumb fan. Row 0 is always the top row. The wiring needs to be:

   • Column 1: A2/PF5
   • Column 2: A1/PF6
   • Column 3: A0/PF7
   • Column 4: 15/PB1
   • Column 5: 14/PB3
   • Column 6: 16/PB2
   • Column 7: 10/PB6
   • Row 1: 4/PD4
   • Row 2: 6/PD7
   • Row 3: 7/PE6
   • Row 4: 8/PB4
   • Row 5: 9/PB5

This is an older picture from when Klavyl still used TRRS jacks, but you get the idea:

10. Use the soldering iron to melt the M3 inserts into the bottom. I used a temperature of 200-250 degrees F. See picture above.

It's the same as the left, but mirrored. Watch out for having resistors only on one side.

Note: the default layout is very custom to me. It is meant for a Mac and has a lot of unexpected changes including swapping around shifted and unshifted keys. Make sure to modify it.

1. Grab a recent version of QMK. I used commit 779c7debcfff1a4a3ad578a0c12bdd50cba11039. Follow the QMK guide to get it set up and compiling.

2. Copy the klavyl dir from qmk/keyboards in this repo to the keyboards dir in QMK.

3. Add a new keymap or adjust the default layout to suit you.

4. Compile and flash with make klavyl:default:avrdude (replace default with your keymap if you made a custom one). You have to reset your Pro Micro to enter bootloader mode by shorting quickly once RST and GND.

Once you flash both halves the first time, later on you only need to flash the half that connects by USB to your computer. The other half just reports what keys are pressed. Only the primary half decides what this means in terms of symbols sent to the computer.