Author Topic: Boston, an Austin-derived compact 120%  (Read 1724 times)

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Offline Pylon

  • Thread Starter
  • Posts: 612
Boston, an Austin-derived compact 120%
« on: Fri, 08 May 2020, 00:59:21 »


The layout for this was inspired by the Austin and also by the 7-row Thinkpad keyboard you find on Thinkpads of the T420 generation and older. The general idea was to make a narrower full-size that retained both the 2u numpad "0" and traditional 2x3 Ins/Del/Home/End/PgUp/PgDn nav block, by expanding vertically. This would allow for an easy transition for full-sized users like me (I've been using full-sized keyboards my whole life)

Much like the Austin, I also generally wanted to use keys that were included in base kits for group buy keyboards, so I wanted to stick to things like a 6.25u spacebar and avoid things like putting a Print Screen key in R2, for example.

This first led to something like this:


I then realized that for the same vertical room I could add a large number of programmable keys above the F-row, and there weren't a lot of 120% keyboards out there, especially not narrow ones, so I figured I might as well add a bunch of keys, resulting in the layout you see on top.

Since this keyboard is an Austin derivative, and because I grew up in Boston, Massachusetts, I decided to name the project "Boston".

Everything is posted on this Github repo:
https://github.com/bluepylons/Boston

General specifications:
  • 121-keys
  • Traditional 2x3 Ins/Del/Home/End/PgUp/PgDn nav block
  • Full-sized numpad with 2u "0" key
  • Uses keys found in GMK base kits (except for programmable keys)
  • USB-C
  • Single-color backlight support
  • Electrical schematic and design largely copied from the Austin
  • Probably will use QMK
  • Controller on a daughterboard that fits under the F5-F8 keys, to reduce prototyping costs (small <100x100mm PCBs are dirt cheap, while large keyboard-sized PCBs are easily $100 per revision) . I currently intend to use an STM32F072 just like the Austin, though I may design a backup controller around an AVR IC (likely AT90USB1287) as QMK appears to be much better supported on AVR.
  • All SMD parts are on the daughterboard, except for backlight LED current-limiting resistors, to keep the main keyboard PCB buildable with through-hole only (unfortunately due to space constraints SMD resistors are necessary if backlight LEDs are to be installed)
  • Case design is TBD - I'm designing the PCB to be tray mountable, but I intend on  mounting via the plate (most likely via top-mount). I most likely will design a couple cases

The keyboard PCB is pretty much done, and I'm working on the controller right now, with work on the case to start after that.  Most recent files are available on the Github repo above.


I might eventually run a GB if this works out well, though that's a ways away.

Many thanks to:
  • The Acheron project - the KiCAD library and the source files for the Austin have been invaluable for designing this board.
  • The designers of the Austin (Driftingbunnies,  PheonixStarr, and Gondolindrim)
  • Gondolindrim, for assistance and feedback with the PCB design, as for running the Acheron project
  • KiCAD, for being an awesome free open-source PCB design tool
  • Keyboard Layout Editor
« Last Edit: Tue, 02 June 2020, 13:37:57 by Pylon »

Offline Maledicted

  • Posts: 1084
  • Location: Wisconsin, United States
Re: Boston, an Austin-derived compact 120%
« Reply #1 on: Fri, 08 May 2020, 09:04:33 »
Cool. Great job. I know the battleship and battle cruiser guys will like this.  :thumb:

Offline funkmon

  • Posts: 131
Re: Boston, an Austin-derived compact 120%
« Reply #2 on: Fri, 08 May 2020, 10:46:38 »
Show Image


The layout for this was inspired by the Acheron Austin and also by the 7-row Thinkpad keyboard you find on Thinkpads of the T420 generation and older. The general idea was to make a narrower full-size that retained both the 2u numpad "0" and traditional 2x3 Ins/Del/Home/End/PgUp/PgDn nav block, by expanding vertically. This would allow for an easy transition for full-sized users like me (I've been using full-sized keyboards my whole life)

Much like the Austin, I also generally wanted to use keys that were included in base kits for group buy keyboards, so I wanted to stick to things like a 6.25u spacebar and avoid things like putting a Print Screen key in R2, for example.

This first led to something like this:
Show Image


I then realized that for the same vertical room I could add a large number of programmable keys above the F-row, and there weren't a lot of 120% keyboards out there, especially not narrow ones, so I figured I might as well add a bunch of keys, resulting in the layout you see on top.

Since this keyboard is an Austin derivative, and because I grew up in Boston, Massachusetts, I decided to name the project "Boston".

Everything is posted on this Github repo:
https://github.com/bluepylons/Boston

General specifications:
  • 121-keys
  • Traditional 2x3 Ins/Del/Home/End/PgUp/PgDn nav block
  • Full-sized numpad with 2u "0" key
  • Uses keys found in GMK base kits (except for programmable keys)
  • USB-C
  • Single-color backlight support
  • Electrical schematic and design largely copied from the Austin
  • Probably will use QMK
  • Controller on a daughterboard that fits under the F5-F8 keys, to reduce prototyping costs (small <100x100mm PCBs are dirt cheap, while large keyboard-sized PCBs are easily $100 per revision) . I currently intend to use an STM32F072 just like the Austin, though I may design a backup controller around an AVR IC (likely AT90USB1287) as QMK appears to be much better supported on AVR.
  • All SMD parts are on the daughterboard, except for backlight LED current-limiting resistors, to keep the main keyboard PCB buildable with through-hole only (unfortunately due to space constraints SMD resistors are necessary if backlight LEDs are to be installed)
  • Case design is TBD - I'm designing the PCB to be tray mountable, but I intend on  mounting via the plate (most likely via top-mount). I most likely will design a couple cases

The keyboard PCB is pretty much done, and I'm working on the controller right now, with work on the case to start after that.  Most recent files are available on the Github repo above.
Show Image


I might eventually run a GB if this works out well, though that's a ways away.

Many thanks to:
  • The Acheron project - the KiCAD library and the source files for the Austin have been invaluable for designing this board.
  • The designers of the Austin (Driftingbunnies and Gondolindrim)
  • Gondolindrim, for assistance and feedback with the PCB design, as for running the Acheron project
  • KiCAD, for being an awesome free open-source PCB design tool
  • Keyboard Layout Editor

In for the group buy cause I'm too dumb to make this. It looks awesome! A compact battleship!

Offline Tactile

  • Posts: 1281
  • Location: Portland, OR
Re: Boston, an Austin-derived compact 120%
« Reply #3 on: Fri, 08 May 2020, 11:16:00 »
Kinda reminds me of something...

241867-0

Offline Rayndalf

  • Posts: 284
Re: Boston, an Austin-derived compact 120%
« Reply #4 on: Sun, 10 May 2020, 21:44:18 »
Kinda reminds me of something...

(Attachment Link)

Those are really cool, I'm guessing it was modeled after the G80-1800 (but not manufactured by Cherry), but they needed some more keys for their (medical IIRC) equipment. A shame the original keycaps are pad printed. The layout adds a lot keys with a pretty minimal increase in size.

Offline Pylon

  • Thread Starter
  • Posts: 612
Re: Boston, an Austin-derived compact 120%
« Reply #5 on: Fri, 15 May 2020, 03:29:29 »
Some various updates:

Finished a first pass at laying out the STM32F072 controller:

 242589-0


I also started working on a top-mount CNC aluminum case in Fusion 360. So far I only have the top half of it somewhat CADed, though I have a general idea of how to make it:

I also will probably design a sandwich and/or 3D-printed case, since CNC aluminum might end up costing more than I'm willing to pay.
242591-1
242593-2

Also I realized there's an awkward space above the Esc key when starting designing a case. After weighing different options (hole, cutout, triangular cutout, angled notch), I  decided to just throw a rotary encoder in there, as I had three unused I/O pins on the controller.

Offline Pylon

  • Thread Starter
  • Posts: 612
Re: Boston, an Austin-derived compact 120%
« Reply #6 on: Fri, 15 May 2020, 03:33:34 »
(and I just realized two halves of the ground plane on the controller aren't connected - remember to always run  DRC folks)

Offline Maledicted

  • Posts: 1084
  • Location: Wisconsin, United States
Re: Boston, an Austin-derived compact 120%
« Reply #7 on: Fri, 15 May 2020, 08:21:04 »
Nice. Looking good.

Offline Pylon

  • Thread Starter
  • Posts: 612
Re: Boston, an Austin-derived compact 120%
« Reply #8 on: Tue, 19 May 2020, 02:57:11 »
Top-mount CNC case is getting there. A couple more details to work out, especially on the plate. Spending a lot of time fighting Fusion 360 unfortunately.

242937-0
242939-1
242941-2
242943-3

I tried to make the case easily machinable on a 3-axis with minimal setups (most pieces should be doable with just 2 setups), and avoided tapers (other than 45-degree chambers) to avoid having to do 3D profiling on a 3-axis CNC (which adds a lot of machining time and expense). That led to a 3-piece case, with the bottom piece serving to set the angle and also as the brass weight.


« Last Edit: Tue, 19 May 2020, 02:59:36 by Pylon »

Offline Pylon

  • Thread Starter
  • Posts: 612
Re: Boston, an Austin-derived compact 120%
« Reply #9 on: Tue, 19 May 2020, 03:29:03 »
One more render from the back, because why not?


242945-0

Offline Maledicted

  • Posts: 1084
  • Location: Wisconsin, United States
Re: Boston, an Austin-derived compact 120%
« Reply #10 on: Tue, 19 May 2020, 10:04:27 »
It is shaping up well.  :thumb:

Offline Rico

  • Posts: 17
Re: Boston, an Austin-derived compact 120%
« Reply #11 on: Tue, 19 May 2020, 10:23:42 »
What a nice project !
Is it you first try ?

Offline Pylon

  • Thread Starter
  • Posts: 612
Re: Boston, an Austin-derived compact 120%
« Reply #12 on: Tue, 19 May 2020, 13:19:39 »
Yeah, this is my first attempt at a custom keeb. And thanks!

Offline Rico

  • Posts: 17
Re: Boston, an Austin-derived compact 120%
« Reply #13 on: Tue, 19 May 2020, 16:22:04 »
Congratulations, it is a very nice keeb :)