30% Prototype Keybaord Design Log

[mrflow3r]

Hello GH, I will be posting the design and build logs for a keyboard that I decided to do for learning purpose.
Eventually I would like to make a quality custom keyboard, but for now expect lots of stupidities and mistakes!

I decided on a basic GH60 layout initially. Then I realized getting PCBs made would be very expensive. I think OSHPark.com quoted me $300 USD .
So I decided to make one that's as small as a keyboard can be. And 30% was hesitantly decided. It's got 32 keys. Alphabets, 1 alt, 1 ctrl, space bar, and the enter key.

The MCU is Teensy 2.0. It made a lot of sense to mod an existing TMK firmware (a huge thanks to its maintainer!).

Using Kicad, learning its quirks, I finalized on a design.
This is the top layer:


And bottom layer:


Then I used PCBWay.com to order the boards. OSHPark.com was still hella expensive. $200 USD. PCBWay all in all came to about $75.
$30 for the board, $25 for shipping, and another $20 for customs and duties. What is impressive is that it took exactly 8 days!
From design submission to my door that is.

Although the service is based in China, I am extremely happy with their service. I have been contacted multiple times to sort out issues.
I have accidentally included 2 drill layers, and they even made a screenshot to explain the confusion:


[update 1]

Here is a shot when I first got my PCBs. I was really excited. I wish the coating of the PCB was better. OSHPark has this shiny coating that doesn't seem to attract dust. PCBWay, while super cheap, it is not a top quality finish:


here is the comparison with HHKB Pro 2. Was surprised how small it was in comparison (which tells how little I knew about what I made lol).


Then I looked for a place to source switches. I have searched for any type of Cherry MX PCB mounted switches, and surprisingly a lot of places were either out of stock or too expensive.
At one point I read somewhere that Gaterons were Cherry-MX compatible. ZealPC came to my attention, and to my surprise I had my switches in less than 48 hours since I ordered:



Btw, Zeal is a super nice guy!

It was long and arduous.  I mean it was fun, but I probably spent more time in searching for the right PCB maker, and the right place to buy the switches, than actually designing the board!

[update 2]

Alright, I began the assembly. Being nervous at the possibility of things not working, I only soldered two switches, and the headers for Teensy.







The TMK firmware code was pretty straight forward. Given enough time, it was easy to figure out the structure of it. I hacked on the GH60 layout.
However, I was not getting any input from any of the 2 switches I soldered!!!! I checked my PCB designs. I checked the pin-mappings. I even made a small circuit to test the switches.

It turns out, my assumption of input/output of the rows and columns was opposite of what TMK assumed. In other words, the direction of my diodes were wrong =(.

After soldering the diode in the opposite direction of the silkscreen, I was able to get the two switches working. I was actually pretty proud of myself at this point haha.



So I happily soldered the remaining switches:





[update 3]

Here is a video of the keyboard in action - https://twitter.com/mrflow3r/status/635338584392790016.
Wanted to make the firmware public, but didn't get a chance to do it today. For now it has a single layer. Will accommodate great suggestions from the comments (much appreciated, again!).
Physically, I am at a stage where I should make a proper case or at least a couple of feet for it. Haven't figured out how to do this yet.
There is still much to be done on the software side. So I will focus on the for the next couple days.

I also realized the Enter key has no trace to a column =(. Rework should be relatively simple. Will update on this tomorrow!
 40-brd.svg (414.3 kB - downloaded 94 times.)

[update 4]
Keycaps here! Clearly I have no clue on the profiles of keys.

[jdcarpe]

Very nice! Looking forward to seeing your progress with this.

[mrflow3r]

Very nice! Looking forward to seeing your progress with this.

Thanks! I will update with more pics tonight

[jbondeson]

Are you planning on doing something like SpaceFn to get function layers?

[GL1TCH3D]

Wondering what the layout is going to be. I feel like the space on the bottom right / left is wasted (to me) but whatever works for you

[user 18]

What layers are you planning on using with this keyboard? I don't see a spot for a shift key on your PCB design, so no way to access uppercase letters. Lack of a function key means you cannot access numbers or symbols either.

I think the design may be workable physically, but unless you're doing something interesting, I think you'll find it difficult to get a usable keyboard.

[jdcarpe]

I think the design may be workable physically, but unless you're doing something interesting, I think you'll find it difficult to get a usable keyboard.

That was basically the reasoning behind my JD40 design. It was the smallest usable rectangular layout I could conceive. Sure, you can go smaller as an exercise, but to make it usable, you really need about 38-40 keys.

[108]

That looks really well designed, great job!

[mrflow3r]

Hey everyone, I got no doubt that 30% is way to small for any real work. I delved into this adventure and my initial goal was to get *anything* working. Learning how design a PCB, figuring out the matrix, finding the parts for the board, selecting a supplier, getting to know the keyboard community (long time lurker but never was engaged), and etc etc. And one of my worries was spending $$$ without getting anywhere. So for this prototype I kept the board as small as possible, to keep the part cost low.  No other noble reason. Just a broken wallet

Will post in more details later.

[mrflow3r]

Wondering what the layout is going to be. I feel like the space on the bottom right / left is wasted (to me) but whatever works for you

LOL I wonder what the layout will be too. My focus was on making the keyboard. Don't have mental capacity to figure out the usability yet haha.

[jdcarpe]

Hey everyone, I got no doubt that 30% is way to small for any real work. I delved into this adventure and my initial goal was to get *anything* working. Learning how design a PCB, figuring out the matrix, finding the parts for the board, selecting a supplier, getting to know the keyboard community (long time lurker but never was engaged), and etc etc. And one of my worries was spending $$$ without getting anywhere. So for this prototype I kept the board as small as possible, to keep the part cost low.  No other noble reason. Just a broken wallet

Will post in more details later.

Just learning how to use KiCAD and producing a viable PCB is a great accomplishment! There is no limit to where you can go from there.


What sizes are the keys on your bottom row? 1.5-6.25-1.5?


Here is your layout:

[GL1TCH3D]

Hey everyone, I got no doubt that 30% is way to small for any real work. I delved into this adventure and my initial goal was to get *anything* working. Learning how design a PCB, figuring out the matrix, finding the parts for the board, selecting a supplier, getting to know the keyboard community (long time lurker but never was engaged), and etc etc. And one of my worries was spending $$$ without getting anywhere. So for this prototype I kept the board as small as possible, to keep the part cost low.  No other noble reason. Just a broken wallet

Will post in more details later.

Just learning how to use KiCAD and producing a viable PCB is a great accomplishment! There is no limit to where you can go from there.


What sizes are the keys on your bottom row? 1.5-6.25-1.5?


Here is your layout:

Show Image

Show Image

Show Image

I'm going to work on my own layouts for this key layout to give OP some ideas.

At OP, is there a reason you chose a 1u shift key?

It kinda feels like you didn't consider the widths xD

[absyrd]

Why the standard space bar?

Looks like a great starting-point, though. Enjoy!

[jdcarpe]

Why the standard space bar?

Looks like a great starting-point, though. Enjoy!

Probably needed somewhere to fit the Teensy.

[BlueNalgene]

Why the standard space bar?

Looks like a great starting-point, though. Enjoy!

Probably needed somewhere to fit the Teensy.

Teensy underneath and a shorter spacebar seems doable if you are most concerned about board economics.

[GL1TCH3D]

Why the standard space bar?

Looks like a great starting-point, though. Enjoy!

Probably needed somewhere to fit the Teensy.

Teensy underneath and a shorter spacebar seems doable if you are most concerned about board economics.

Yea, if he had a short spacebar and kept the bottom row to 3 keys hed have space on the bottom left/right to fit it.

[absyrd]

This is why I asked. I have no clue how y'all fit this stuff. Thanks for expanding upon my noob question.

[GL1TCH3D]

This is why I asked. I have no clue how y'all fit this stuff. Thanks for expanding upon my noob question.

My first guess would be that he prefers a standard spacebar rather than a short one at 2u or something. Also judging by the layout he should be able to use a regular keyset for this.

[jacobolus]

So basically a Texas Instruments TI-99/4A but without the number row?

https://en.wikipedia.org/wiki/Texas_Instruments_TI-99/4A

[BlueNalgene]

This is why I asked. I have no clue how y'all fit this stuff. Thanks for expanding upon my noob question.

It is somewhere between tracing a line in the sand and shoving Christmas lights back into the box.

[jdcarpe]

So basically a Texas Instruments TI-99/4A but without the number row?

Show Image

https://en.wikipedia.org/wiki/Texas_Instruments_TI-99/4A

That's what it reminded me of, as well. Of course, that may be because my first computer was a TI-99/4A. :)

I have some SA caps, uniform row 3 of course, that were made for the later version of the 4A. You can tell that SP, well Comptec I suppose, made them, because they look exactly like modern SP SA caps. They are made for some odd Alps-compatible switch with angled stems from a late version of the 4A keyboard.

[mrflow3r]

Are you planning on doing something like SpaceFn to get function layers?

Truth to be told, I hadn't thought about the layout =P. Space + Fn to switch layers sounds pretty good.

Hey everyone, I got no doubt that 30% is way to small for any real work. I delved into this adventure and my initial goal was to get *anything* working. Learning how design a PCB, figuring out the matrix, finding the parts for the board, selecting a supplier, getting to know the keyboard community (long time lurker but never was engaged), and etc etc. And one of my worries was spending $$$ without getting anywhere. So for this prototype I kept the board as small as possible, to keep the part cost low.  No other noble reason. Just a broken wallet

Will post in more details later.

Just learning how to use KiCAD and producing a viable PCB is a great accomplishment! There is no limit to where you can go from there.


What sizes are the keys on your bottom row? 1.5-6.25-1.5?


Here is your layout:

Show Image

Show Image

Show Image

It is 1.25 - 6.25 - 1.25.
And thanks for the layers. I will code exactly that up! Honestly I have gave zero thought on the layout of this keyboard.
My goal was literally just to get some sort of keyboard to work. If could have had 10 keys for the purpose!
That said, it is great to know that there is a set of layers that makes my keyboard functional.

[mrflow3r]

Why the standard space bar?

Looks like a great starting-point, though. Enjoy!

Thanks! 6.25u is a standard space bar? Honestly I didn't have any idea on different sizes of the keycaps.
I will publish all my work. And I hope to build better keyboards from here on. It's definitely enjoyable!

[mrflow3r]

This is why I asked. I have no clue how y'all fit this stuff. Thanks for expanding upon my noob question.

My first guess would be that he prefers a standard spacebar rather than a short one at 2u or something. Also judging by the layout he should be able to use a regular keyset for this.

Well, I used whatever size that looked like a standard size. 2u is way too short for my liking. It looks weird!
And I haven't received my keycaps yet (bought some white PBT keycaps for cheap on eBay a few weeks ago).
Regular keycaps should work fine, unless I didn't space the switches correctly.

[mrflow3r]

So basically a Texas Instruments TI-99/4A but without the number row?

Show Image

https://en.wikipedia.org/wiki/Texas_Instruments_TI-99/4A

Haha that thing is a beauty! Haven't seen it ever before. Yet I feel strangely drawn to it. Personally TI is one of my favorite companies.

[Oobly]

That's a very cute looking little board! Nice. And with JD's layouts in can be usable, but I agree that splitting the spacebar and adding a couple keys there would make it far more useful.

This is the minimalist layout I came up with when designing a super compact but usable board:


I found I really need ,. and Backspace on my default layer, so I kept it a little wider than yours (and since it's also designed for others to use I have both Shifts), by about 1x key spacing overall. Early prototype made from a hacked up Cherry G80 PCB:


These tiny boards are surprisingly fun to type on. Somehow liberating. I think that after using yours for a little while you're going to be interested in making a Version 2

[mrflow3r]

That's a very cute looking little board! Nice. And with JD's layouts in can be usable, but I agree that splitting the spacebar and adding a couple keys there would make it far more useful.

This is the minimalist layout I came up with when designing a super compact but usable board:
(Attachment Link)

I found I really need ,. and Backspace on my default layer, so I kept it a little wider than yours (and since it's also designed for others to use I have both Shifts), by about 1x key spacing overall. Early prototype made from a hacked up Cherry G80 PCB:

Show Image

These tiny boards are surprisingly fun to type on. Somehow liberating. I think that after using yours for a little while you're going to be interested in making a Version 2 :)

Yes I am already thinking of the version 2! Like you said, I think I need a few more keys to be more usable. It will still be very portable though. Mini keyboards are really fun and interesting.

 Thanks for the suggestion on the layout. I agree that a backspace is important. It was an oversight from me really (forgot the backspace..)  Splitting the space bar felt alien to me until last night, but it has grown on me LOL.

And thanks for reading my log. Never thought I'd get this much support from GH!

[joey]

WHY HAVEN'T YOU ASSEMBLED IT YET?!

[mrflow3r]

WHY HAVEN'T YOU ASSEMBLED IT YET?!

It is assembled. I will update later today or through the week!

[trenzafeeds]

WHY HAVEN'T YOU ASSEMBLED IT YET?!

It is assembled. I will update later today or through the week!

I'm really excited to see how it looks! Seems like an interesting little project that I would consider doing using hand-wiring (to cut costs).

[mrflow3r]

WHY HAVEN'T YOU ASSEMBLED IT YET?!

It is assembled. I will update later today or through the week!

I'm really excited to see how it looks! Seems like an interesting little project that I would consider doing using hand-wiring (to cut costs).

Thanks I am having a tonne of fun with this! I got spare PCBs. If you want one I can send one to you for free. Mailing shouldn't cost too much (in NA).

[trenzafeeds]

WHY HAVEN'T YOU ASSEMBLED IT YET?!

It is assembled. I will update later today or through the week!

I'm really excited to see how it looks! Seems like an interesting little project that I would consider doing using hand-wiring (to cut costs).

Thanks I am having a tonne of fun with this! I got spare PCBs. If you want one I can send one to you for free. Mailing shouldn't cost too much (in NA).

Show Image

That would be too cool! PM'd you.

[mrflow3r]

WHY HAVEN'T YOU ASSEMBLED IT YET?!

It is assembled. I will update later today or through the week!

I'm really excited to see how it looks! Seems like an interesting little project that I would consider doing using hand-wiring (to cut costs).

Thanks I am having a tonne of fun with this! I got spare PCBs. If you want one I can send one to you for free. Mailing shouldn't cost too much (in NA).

Show Image

That would be too cool! PM'd you.

Got it. I will update the log later today to explain stuff that could have been different. I made small mistakes on the design here and there. If you can hand wire a keyboard, you can work around these issues too.

[paicrai]

that is an interesting little doodad
do it in pink :3

[neverused]

You should next the function layers (ie use FN1 to access FN2 which could toggle a punctuation/numeric layer.) I think some WASD UV printed keycaps would be helpful to record those mappings.

[mrflow3r]

Updated!

that is an interesting little doodad
do it in pink :3

Do the PCB in pink? Ya I think I want to focus on the aesthetics of the PCB for the version 2. Pink would be hot

 

You should next the function layers (ie use FN1 to access FN2 which could toggle a punctuation/numeric layer.) I think some WASD UV printed keycaps would be helpful to record those mappings.

Ya I definitely have to figure out how function layers work in TMK. Right now my hacked-up TMK code does only 1 layer LOL. Once I figure it out, I will clean up the code and make my firmware available. It's on my to-do list.

[mrflow3r]

I will post a video of my keyboard in action later today or tomorrow!

[Zustiur]

Impressive start. I am struggling with kicad. Please tell us everything you learned.

[mrflow3r]

Impressive start. I am struggling with kicad. Please tell us everything you learned.

Thanks! In which point are you struggling at? I will my best try to answer

[Zustiur]

I think the main thing that I'm stuck on is footprints. I downloaded the resources from the Living PCB Thread but they seem to be from an older version of KiCad. Nothing seems to match up the way I expected it too. Where did you get your MX switch and teensy footprints from?

[BlueNalgene]

I think the main thing that I'm stuck on is footprints. I downloaded the resources from the Living PCB Thread but they seem to be from an older version of KiCad. Nothing seems to match up the way I expected it too. Where did you get your MX switch and teensy footprints from?

Hey person, good luck on your KiCAD journey.  It has been kind to me. 

Here is a link to some switch files for you.  I want to say Joey Quinn made them, but he may have just linked it to me.  There is a living PCB design thread that may be of use to you, here.  Check JDCarpe's sticky in the Making Stuff Together! subforum for the major threads, and search around for more.  There is a lot of help to be had with this lot of nerds. 

Edit: I forgot to mention.  Sometimes people use weird pin names for their components and footprints.  If you are having trouble with footprints looking weird, I check to make sure everything matches up correctly between Eeschema and PCBnew bits.  If you see simple boxes for components in the schematic instead of the pretty symbol you were expecting, then your library is directing to the wrong location for that module.

[mrflow3r]

I think the main thing that I'm stuck on is footprints. I downloaded the resources from the Living PCB Thread but they seem to be from an older version of KiCad. Nothing seems to match up the way I expected it too. Where did you get your MX switch and teensy footprints from?

Hey! Can you show me the link to the resources in that thread? I mostly started from this page - http://deskthority.net/wiki/KiCAD_keyboard_PCB_design_guide.
On the bottom, it links to a library of components - https://github.com/BathroomEpiphanies/KiCAD-Keyboard-Tutorial.

That's what I used to design this PCB.

I think the main thing that I'm stuck on is footprints. I downloaded the resources from the Living PCB Thread but they seem to be from an older version of KiCad. Nothing seems to match up the way I expected it too. Where did you get your MX switch and teensy footprints from?

Hey person, good luck on your KiCAD journey.  It has been kind to me. 

Here is a link to some switch files for you.  I want to say Joey Quinn made them, but he may have just linked it to me.  There is a living PCB design thread that may be of use to you, here.  Check JDCarpe's sticky in the Making Stuff Together! subforum for the major threads, and search around for more.  There is a lot of help to be had with this lot of nerds. 

Edit: I forgot to mention.  Sometimes people use weird pin names for their components and footprints.  If you are having trouble with footprints looking weird, I check to make sure everything matches up correctly between Eeschema and PCBnew bits.  If you see simple boxes for components in the schematic instead of the pretty symbol you were expecting, then your library is directing to the wrong location for that module.

Yes, check the work triple times! The Teensy 2.0 in the component library has the pins actually in the opposite order. This is not much a problem, but I had to remap my pins in the firmware. It was pretty confusing for a while!

I will also update the log with my Kicad files and firmware code this weekend. I am just tied up on personal matters tonight.

[Zustiur]

Here is a link to some switch files for you.  I want to say Joey Quinn made them, but he may have just linked it to me.  There is a living PCB design thread that may be of use to you, here.  Check JDCarpe's sticky in the Making Stuff Together! subforum for the major threads, and search around for more.  There is a lot of help to be had with this lot of nerds. 

That's the thread I started with, but all the resources provided seem to be for an older version of kicad and it gives me weird errors when I try to use them. (See my posts in the Living PCB Design thread for more detail)

Hey! Can you show me the link to the resources in that thread? I mostly started from this page - http://deskthority.net/wiki/KiCAD_keyboard_PCB_design_guide.
On the bottom, it links to a library of components - https://github.com/BathroomEpiphanies/KiCAD-Keyboard-Tutorial.

Yeah, I looked at that page a lot too. Thanks for pointing out the tutorial link. Even knowing it was there on the DT page I still took a long time to find the link
The resources I referred too are all listed on the first page of The Living PCB Design Thread

[mrflow3r]

Here is a link to some switch files for you.  I want to say Joey Quinn made them, but he may have just linked it to me.  There is a living PCB design thread that may be of use to you, here.  Check JDCarpe's sticky in the Making Stuff Together! subforum for the major threads, and search around for more.  There is a lot of help to be had with this lot of nerds. 

That's the thread I started with, but all the resources provided seem to be for an older version of kicad and it gives me weird errors when I try to use them. (See my posts in the Living PCB Design thread for more detail)

Hey! Can you show me the link to the resources in that thread? I mostly started from this page - http://deskthority.net/wiki/KiCAD_keyboard_PCB_design_guide.
On the bottom, it links to a library of components - https://github.com/BathroomEpiphanies/KiCAD-Keyboard-Tutorial.

Yeah, I looked at that page a lot too. Thanks for pointing out the tutorial link. Even knowing it was there on the DT page I still took a long time to find the link
The resources I referred too are all listed on the first page of The Living PCB Design Thread

Ya with the materials on the wiki and from the Living PCB thread, I think you have all you need. That said, the library and foot print management in Kicad is something out of this world. It literally blew my mind as how confusing it was to set it up. Are you still having trouble assigning the footprints?

[mrflow3r]

Updated with a video!

[mastercontrol90]

Here it is a gift for you my friend! BTW check the switch positions on your pcb: the switches altogether are not centered relatively to the center of the pcb so all the keyboard itself is not centered. Try also to do a more "precise" pcb border, like 90 x 40 (this is a totally arbitrary measure for example purpose), instead of 8x,xx x 4x,xx mm , ok? Other than that is more than ok



DXF file for laser cut
 30% kb plate_final.dxf (381.39 kB - downloaded 124 times.)

[trenzafeeds]

So the sense I'm getting is that once you solder the diodes on wrong, it works pretty damn well! Congrats! 

[mrflow3r]

Here it is a gift for you my friend! BTW check the switch positions on your pcb: the switches altogether are not centered relatively to the center of the pcb so all the keyboard itself is not centered. Try also to do a more "precise" pcb border, like 90 x 40 (this is a totally arbitrary measure for example purpose), instead of 8x,xx x 4x,xx mm , ok? Other than that is more than ok

(Attachment Link) (Attachment Link)

DXF file for laser cut
(Attachment Link)

Hawt damn thanks a bunch! This is really cool! When I decided to make the PCB, didn't think I would get much help on it. This is really nice. I will send you a V2 when it's done. It's on me!

[mastercontrol90]

Here it is a gift for you my friend! BTW check the switch positions on your pcb: the switches altogether are not centered relatively to the center of the pcb so all the keyboard itself is not centered. Try also to do a more "precise" pcb border, like 90 x 40 (this is a totally arbitrary measure for example purpose), instead of 8x,xx x 4x,xx mm , ok? Other than that is more than ok

(Attachment Link) (Attachment Link)

DXF file for laser cut
(Attachment Link)

Hawt damn thanks a bunch! This is really cool! When I decided to make the PCB, didn't think I would get much help on it. This is really nice. I will send you a V2 when it's done. It's on me!

thanks to you man! Fix all the problems on your next Pcb and I'll do another case for it

[mrflow3r]

Here [1] is the working firmware for this project. Haven't had the chance to clean it up yet unfortunately. My town has lot electricity =(

[1] https://github.com/b1gtuna/tmk_keyboard/tree/b1gtuna-30