Manuform Dactyl
WHAT YOU NEED PARTS
Keyboard case
Keyboard case bottom
(2x) Pro Micro controllers
(2x) TRS/ TRSS ports
(10x) Brass thread inserts
(64x) Cherry MX switches
(3 feet) Wire
TRS cable
1 PRINT THE CASE
The first part of the build is simply printing out the case. The model is approximately 6 x 7 x 2 inches, so it will fit on most popular FDM printers with a bed over this size. We have access to a few 3D printers, one of which has a 20 x 20 x 20-inch bed, so we used that. With supports each side, it took around two days for each half to print. This time could have been reduced by having fewer walls and less infill, but we wanted to make sure that everything was as solid as possible. We used four walls and 30-percent infill. In total, we used just under 0.7lb of filament. The filament cost us US$22 for 2.2lb, making the price of the case US$7, not including the few cents of electricity we used. We also printed out a couple of wrist rests at the same time.
2 TIDY THINGS UP
Once the prints were completed, we needed to remove the supports. The free 3D file that we’d downloaded to use for our prints had small clips that were supposed to help with cable management. They were horrible, however, and would just snap off while they got tangled up with the supports, and then also got in the way when soldering. That being the case, we simply used some cutters to chop these off so that the inside was clear. This way, we can just keep the wiring tight and neat, without having to worry ourselves about cable management.
The cases are 3D printed, of course, so they are not perfect. We could sand them down, use filler, and then paint them, but to be honest, we actually like the rustic look a little bit more. The keyboard is obviously home-made, and if everything looked too perfect, we wouldn’t get the usual “Wow, did you make this?!” questions we crave so much.
3 ADD THE INSERTS
Once the two case halves were completed, we wanted to make sure it was easy to attach the bottom half to the top. To do this, we used threaded brass inserts. These ones are M3, which enabled us to use spare screws from a PC case that we’d found. To get the brass inserts into the pre-determined holes, we used a soldering iron and a razor blade. We placed an insert into the hole, then put the tip of the iron into the threaded insert, and pushed while the heat melted the plastic. To stop the insert from coming back out
when we removed the soldering iron, we used a razor blade. This meant that it would stay flush with the rest of the case. Once the plastic around the insert cools down, it grips on to the outer contours of the insert, and holds it in place. Magic.
Next, the switches!
4 SLOT IN THE SWITCHES
For this version of the Dactyl, Cherry MX-style switches fit perfectly. Kailh-style switches would fit, too, but they’re a bit more of a squeeze, and you would probably have to use glue or something similar to keep them from popping out. We decided to use Cherry MX switches—one of our favorites, in fact, the Cherry MX Greens. These switches are very tactile, with a rather loud click, perfect to use in the office to annoy any colleagues who may be working in the vicinity.
Inserting all the switches in the case is very easy. It’s just a case of pushing them into the holes; the ridges on the inner edges of the holes clip on to the switches nicely. When choosing your switches, it doesn’t matter if they’re plate-mount or PCB-mount, because once they’re all in place, it makes no difference in this application. If you do get PCB-mount, you can cut the PCB-mount plastic pins off to give you more room for the wiring.
5 PREPARE THE DIODES
Soldering the diodes to the switches is the next step. It’s really important for the diodes to be soldered in the correct orientation. Diodes are there to allow the current to flow one way, but not the other. This enables the controller to figure out exactly which switch you pressed, because it knows where the signal stopped. The switches are laid out in rows and columns, and by using diodes, it is like giving each switch a grid reference, which equates to knowing which key has been pressed. The diode needs to have the black end facing away from the switch. It is easiest to solder the diode directly to the pin, and even easier if you make a hook to allow the diode to wrap around the switch pin before adding flux and solder.
6 SOLDERING ON
Put the diode on the pins closest to the controller, because it makes it easier to route the cables. Once the diodes are connected, you can then solder them in series, so that you will be left with one end per row closest to the controller ready to solder. For our keyboard, this means six wires for the rows.
7 ACQUIRE SOME WIRE
We’re doing the columns next. For this, we need some wire. We acquired a spare Ethernet cable that was carelessly left hanging from the back of this writer’s PC. We cut off the end and stripped the outer insulation to reveal a whole bunch of wires. This is perfect for this application, because it’s thin enough to be worked with and is more than ample to carry the low voltage. It also has eight different colors, so you can color-code the columns easily.
8 STRIP SEARCH
Measure the wire against the switches, so you can figure out where the insulation needs to be removed, then use a pair of wire strippers to remove sections of the insulation. This allows for the wire to be soldered to the switches, while keeping enough insulation on the wire to prevent any short circuits. You need one wire per column, which results in six more wires. Solder the switches in series again, making things rather neat and tidy, even with our amateur soldering.
9 MICROCONTROLLER OPTIONS
We’re going to solder the microcontroller next. You need two controllers for a split keyboard—one for each side of the board. If you are building a standard keyboard, macro board, or numpad, you only need one. Pro Micros are ATmega32u4 8-bit microcontrollers with an integrated USB controller, and are perfect for this kind of application. We are using some cheap clones from Amazon, which were $18 for three, making them $6 each—bargain. The downside to these clones is that you need to install USB drivers for them before they work correctly. With some other controllers, you won’t need to do this. Using the pinout, we soldered the rows and columns into the correct points on the Pro Micro.
10 WIRING DONE!
Both sides use the same pinout, but the wiring is mirrored. Once you have finished soldering and slid the controllers into their little holders, it should look something like the image (top-left).
11
BOTTOM BUSINESS
As we have access to a laser cutter, we decided to make the bottom of the plate out of 3mm clear acrylic. This meant that we could see all of the internal wiring, and show off the
fact that we made the keyboard ourselves. We countersunk the holes and added some little rubber feet.
12 CREATE A CABLE
We made a quick TRS cable with a couple of connectors, a borrowed micro-USB cable, and some sleeving that we happened to have left over from our sleeving feature to finish the build. We made it match the color scheme and ensured it was just long enough for the keyboard to sit comfortably on the desk without disconnecting. We then added some blank keycaps to finish the look.
13 FLASH POINT
Now the physical side of the keyboard is complete, it is time to flash the microcontrollers, so that we can actually use our new board. We thought this part was going to be easy, because the QMK software project (https://qmk.fm) has released a nifty program known as the QMK Toolbox, which usually makes things simpler, as it already has predetermined open-source firmware layouts for custom boards like ours, including handwired Dactyls. But alas, things didn’t work quite as intended.
The problem is fairly elementary. Some clones and Pro Micro controllers currently have a Schottky diode in them, which allows too much voltage to leak backward to the VBUS. This means that both controllers think that they are plugged in, even though only one is. In turn, this confuses the controllers, and makes them believe that they are both the primary controller, when in fact one needs to be the primary and the other the secondary controller.
14 PROBLEM SORTED
To fix this issue, we had to flash the controller using a slightly different method from the one we’d originally planned to use. First, we made the file using the website (http:// bit.ly/MPCQMKConfig). We then compiled and downloaded the file, installed QMK MSYS (http:// bit.ly/ MPCMSYS), and then ran the QMK Setup command. This means we are now able to flash the keyboard. Before doing this, though, we went to the “config.qmk” file and opened it with Notepad++.You need a program that supports Unix line endings— this works, and it has the added bonus of being free. Once we open the config file, we add this single line:
#define SPLIT_USB_ DETECT . This fixes the problem that we outlined above. It took far too long for us to figure this out, though, and to be honest was far too simple a fix.
15 FLASH THE FILES
Now we’re ready to flash the files through QMK MSYS. To do this, we connect the primary (left side) keyboard to the secondary part (right side) using the TRS cable, then plug a micro-USB cable into the left side. Run the following command:
qmk flash -kb handwired/dactyl_ manuform/5x6 -km default -bl avrdudesplit-left
Depending where the file is saved, the command changes. Reset the controller by shorting the RST and GND terminals on the Pro Micro. QMK MSYS then flashes the left side. Remove the micro-USB cable, but keep the TRS cable in place. Plug the micro-USB into the right side and run:
qmk flash -kb handwired/dactyl_ manuform/5x6 -km default -bl avrdudesplit-right
Reset the microcontroller again and wait for it to finish. Once it is finished, you plug the micro-USB back into the primary side, and you should be good to go.
Although flashing sounds easy enough, it does take a lot of research, depending on the board and layout. However, if you are confused at all, visit the QMK Discord server, and speak to the people in the Help section. They are extremely helpful, and gave us some pointers when we were struggling to flash the keyboard for a few days due to an issue that we had never seen previously.
16 CRAZY KEYBOARD
That’s the keyboard done and dusted. Now we just have to spend a few months learning how to use it! The Manuform Dactyl is supposed to be very comfortable to use and can increase typing speed while staying ergonomic. Only time will tell if this is true or not, but one thing is for sure: It looks amazing.