Back in the mid-90's, I got myself a Cherry keyboard with MX blues. It was great. I used it a lot. I never took it in to work, though, and at the start of this year, after my KVM broke, they replaced my cheap and flimsy rubber dome with something far, far worse. Something that might have cost 2 quid to make. I looked at it in horror, and decided something must be done.
I wanted a mechanical keyboard for work, and something based off my old Cherry seemed perfect. Why not use the Cherry itself?
- It didn't do USB. It didn't actually do PS/2, either, having an AT plug and an adapater
- It lacks Windows keys, which are convenient
- Actually, a couple of keys had started to flake out. That definitely needs fixing
- It didn't have a metal plate, which seemed a shame
- It wasn't tenkeyless and, well, I never use the number pad and do use a mouse on the right, so that's a bit sub-optimal
So, I decided to take the old Cherry, and reuse the switches and keycaps. This project has taken rather longer than I expected (and been more expensive!), so I should probably have just bought a nice new mechanical, rather than wait so long, using the horrible work keyboard, but it's certainly been a fun project.
As I'd never done any custom keyboard stuff before, I just followed a very simple variation of the Phantom design.
More details in the sections below, but the basic steps ran something like this:
- Got customised plate lasered
- Soldered the Teensy microcontroller to the Phantom PCB
- Installed diodes
- Painted plates
- Installed switches and stabilisers
- Soldered up the switches
- Made case
The instructions at http://deskthority.net/wiki/Phantom_instruction_guide are very good and should give you everything you need, but I thought I'd just share my thoughts and experiences.
Edited original file (probably the same as http://deskthority.net/resources/file/1507) in Inkscape. On importing, scaled up by 25.4 to convert from inches to millimeters. All I did was remove the plate holes for keys I'm not using (since I'm not adding a cosmetic top layer), and add a larger surround with screw holes (since I'm not using the standard cases). Result is "tkl-rim.dxf".
After a few quotes, and recommendations on the web, the plates were then laser cut by Yorkshire Profiles. This plate was cut with a couple of others to get the price down a bit. Would still be a lot better in a big group buy. The finishing was pretty raw (as expected).
My original plan was to leave it raw, but then I decided to go for a painted surface. Rubbed with fine grades of steel wool, then sprayed with etching primer and plain white spray paint.
Used Autotek AT000EP500 500ml Etch Primer and Hammerite Smooth White Metal Paint. Important things I learnt were:
- If steel wooling with the keyboard on cardboard and a dust sheet, don't just clean the bits off the keyboard and get on with spraying. The spray can will blow the bits everywhere. Clear off the surface too, duh!
- Make sure you wear a mask if you don't want funny-coloured snot (previously learnt sandpapering a painted surface).
The surface coating wasn't absolutely perfect, but it's good enough, and the bits without the tiny blemishes do look kinda awesome.
Bought from MechanicalKeyboards website.
Bought in a group buy from Deskthority.
Got the teensy software from http://www.pjrc.com/teensy/loader_mac.html
https://github.com/tmk/tmk_keyboard looks awesome, but needs the tools to build
Ended up using phantom_ansi_iso.hex from https://github.com/BathroomEpiphanies/AVR-Keyboard
It's very important to solder the Teensy in correctly. Solder the Teensy as low onto the main PCB as you can, since the Teensy sticking out the back is the limiting factor on the the depth of your keyboard, which you probably want to make quite thin. At the very least, take any plastic blocks off the headers. Ideally, solder the thing flat against the main board.
Once soldered in, you need to really trim the soldered connections as flat as possible on the switch side, since they control how low you can put the switches that overlap the Teensy. You want as near as possible to flat.
Flashed it, and it came up as a keyboard. Once the Teensy was soldered to the main board, bridging the appropriate pads produced the expected keystroke. Hurrah!
Bought in bulk off ebay. Soldered on, and then the keys tested.
Also installed a couple of 5mm LEDs with 220 ohm resistors for the locks.
Bought some plate-mounted Cherry stabilisers. Royal Mail lost them.
Tried sawing off PCB-mounted stabilisers (like you can saw pins off the PCB-mounted keyswitches to create ones suitable for plate-mounting). Put them in the board. Looked about right, but when I stuck a keycap on the alignment was clearly wrong as the keys stuck.
Got some more plate-mounted Cherry stabilisers. These ones arrived, and did the business. It took a while to work out the best way to mount them. They are pushed in from the keycap side, having first passed the metal bar through the cut-out slot from the cap side to the soldering side.
Vintage MX blues taken from my old Cherry keyboard (bought in 1995). Opened them all up, took them apart got the accumulated fluff out with a loupe, a pointy stick and Rodico.
Afterwards, tested them all for correct switching and correct feel - the keyboard had had about a decade of constant use, so some of the switches didn't feel as nice as the others. Since this is a TKL build, and the original keyboard was full-size, I could take a few out of circulation.
Taken from my old Cherry keyboard. (They're doubleshot. This is not something I'd realised at first, so I was somewhat surprised after the first few years that there was really no sign of wear to the labels...).
They were quite grubby after all their usage, but they quicky cleaned up when I scrubbed them with water and washing-up liquid, using an old toothbrush.
For the modifiers, I needed to add 1u Cherry profile Windows keys. In the end, I bought a Qwerkeys end-of-stock set of brightly-coloured modifiers that include the 1u. The bright colours rather change the look of the design (not quite so subdued and minimalist any more), but they are rather fun. The profile's a not-bad but not perfect match (the Cherry keys modifier row profile is the old profile that's not done any more).
I built a wooden case. The main thing I learnt here is that I'm no good at woodwork. Wood, without the right tools, is very slow going to make right. Oh, and it's very easy to get wrong - indelible dents, things too short/thin/narrow, things gone non-square and difficult to get back. Splintering when you least expect it.
Appropriate tools help. Experience plus power tools would have made it a doddle. I bought increasingly non-inappropriate tools, including a mitre saw, chisel and tiny little files (needed for doing the connector recess). I bought a Dremel 231 router set-up for my Dremel tool. This has incredibly bad write-ups on the web as being flimsy as anything, but was perfect for my needs of creating recessed areas in small pieces of fairly soft wood. Eventually I got not bad at planing, too.
The other thing I learnt is that you can take four straight pieces of wood together and get something non-planar as a result. Argh. A keyboard that wobbles. So, in between the wooden frame and the base, I added a shim to correct the wobble. Super ugly.
To put it together, I used appropriate glue. The keyboard top (screwed into place) and bottom (a metal sheet covered in baize to make it rest nicely on the work top, held in place with nail) do the real job of holding it together.
The case is clearly the weakest link, something I'm not terribly proud of, but I don't have the time (or energy!) to really make it lovely.
I wanted a USB socket on the case, so I ended up creating an extension for the Teensy by cutting a cable in half and soldering it onto a socket embedded in the case. It didn't work initially, until I found out that either the colours in the cable or the socket pin-out or something was lying. Debugging was aided by comparing a cable that worked, vs my hacked-up cable, with a continuity tester. In my case, it appears I swapped D+ and D-, and once these were reversed it worked fine. The socket was then glued into the case.
The internal plug that plugged into the Teensy needed to have its plastic cut off in order to fit into the available internal space. Snip snip snip...
I varnished the wood. Protip: A matt clear varnish will make you wonder why you bothered, since it's basically invisible.
In the end, it looks in no way professional. However, I can live with the rustic look - I'm quite happy to have a keyboard that makes it clear I built it myself, and it still does the job for typing upon.
The Phantom design tries to be a jack of all trades. It covers ISO and ANSI, plus a few other custom funky things, with 1u and 1.5 Windows keys. This does lead to a few ugly things - the wide switch hole for caps lock, the space bar with multiple stabiliser cut-outs, various bits on the PCB where the holes are a bit ick, etc.
Overall, it does a pretty good job, but if I were to do this again I'd probably tidy up the plate a little bit more. I'd not try to redo the PCB though!
On of the more painful bits is quite how thick the keyboard has to be because of the Teensy and the way it's mounted. As I'm reasonably confident with my soldering, /if/ I were to produce my own PCB, I think I'd directly solder a microcontroller to the board, saving the depth. If I could find an appropriate easy-to-solder SMT microcontroller, I guess.