I don't. You seemed to be worrying about GPIO availability.
There are literally 3 pins left unassigned on the kit, despite them not being marked on the "default pinout" picture. It only describes "user-serviceable" pins that are used in default pinout. No markings next to the pin doesn't mean it's unused.
I was referring to J1 pins as they're needed for the pad card. I assume only 0_2, 0_3 and 0_4 are needed on J2 and the remaining 19 GPIOs could be used for other purposes, right?
About the layout, would 90° rotated and stretched pads be a good idea for the bottom row? I noticed IBM used stretched pads for different 3741/2 enter configurations.
Anyway, if you plan to attend the big meetup - I'll be there, we can chat about that.
Edit: looked into Location field. ^ doesn't seem likely.
Did you and wcass meet and discuss the project?
Contemporary sticks have 4 terminals - see patent drawings for the schematics, but there are 4 resistors in addition to the strain gauges. It is humanly possible to desolder those and have a common ground + strain gauge outputs out, but it involves desoldering 0603 SMD resistors. Which is easy if you have a JBC with tweezers, but otherwise not.
I see. I don't think removing them is a big deal though, they're pretty accessible. You could twist them off with flush cutters in seconds or use the large tip + solder blob technique.
I disassembled the various models I have, perhaps someone'll find this useful:
None of those I have are ideal, only the 230e one could potentially be filed down to fit. It's a nice compact shape for other projects though.
Unless someone knows of an appropriate trackpoint model for this project I'll put that on hold for now. $30 for the whole assembly is a bit steep.
The reason I haven't posted for a while is that I wanted to try out an idea for a fully CNC routed case. I'm impressed by the speed and surface quality I can get out of the machine I've been getting familiar with for the last couple of weeks and this seems like a great learning project. I'd much rather spend my time gaining CAM/CNC experience than cursing at 3dprinters
My current design consists of three parts:
- Top case with ~4mm integrated plate
- A base to which the top case, sense and controller PCBs attach. The sense board on top and the controller board in a wide cutout on the bottom with a rear cutout for the wires connecting them.
- A rear bottom piece which acts as a lid for the controller board and port cutout for the type-c port. The smaller size gives me enough Z clearance (~70mm) to flip the piece for rear port cutouts, perhaps a slide switch for BLE etc. This piece could also be made thicker for permanent case tilt.
For now I'll be doing hardwood, I'm planning to cut aluminium later on but as it's more expensive and less forgiving this isn't exactly an ideal beginner project for that
A top mounted plate version would also be possible if a rolled/milled plate ever gets made. Milling the current plate requires ~9.5mm thick stock, I'm planning to get some POM for the beamspring project which I might try out for this.
As mentioned before I'll share the complete CAD data and also the toolpath setup in case someone wants to make their own or customize the model. For CAM I'm using FreeCAD's path workbench and while it's quite capable there are still workarounds required for some toolpaths. I'll most likely script parts of it, for example use lists of X offsets for the switch operations so that custom bottom rows are an easy change.
As for fasteners I'll initially just M3 tap the wood, but these
seem ideal. Unfortunately they're not widely available and quite expensive in Europe.
I also plan to use 3x20mm dowel pins for precise top/bottom case alignment, they're ~€0.1 each so it seems like the best solution.
Here's a Chyron style navigation cluster SKCM test case I did using walnut and beech, a good indicator of what to expect: https://imgur.com/a/uFHMYgn
⌀6mm endmill, 8mm depth of cut https://gfycat.com/defiantcoldkitfox
Assembled (with sound): https://gfycat.com/agreeableenchantedanole
Controller PCB proposal
I also did a PCB mockup to fit the case:
I personally prefer the longer, centered port version.
DMA: Would you be interested in doing the board layout for this? An optional BLE and battery charging section would be really cool
The battery cavity is currently ~130x30x5mm, I'm considering extending it to fit this 135 x 45 x 5 mm battery: https://www.olimex.com/Products/Power/B ... PO3000mAh/
Let me know what you think, and if there are specific features you'd like to change or add.