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geekhack Projects => Making Stuff Together! => Topic started by: coniurare on Thu, 10 September 2020, 19:07:04

Title: Sturdy solderless board with wire-wrap tool possible?
Post by: coniurare on Thu, 10 September 2020, 19:07:04

Hello,

after recently learning about wire-wrap connections (https://en.wikipedia.org/wiki/Wire_wrap) I'm wondering if it's feasible to build a relativly sturdy custom keyboard without using solder or a PCB and only with wire wrap connections, if direct wiring is used?

For example a small 36 keys keyboard which would use a Teensy++ 2.0 with soldered headers for the wire wrap using 30 awg wire. The mcu headers seem large enough even for multiple wraps around a single pin, but what about the switch pins? Would those be large enough? Looking at vvp's Kathy (k80CS) keyboard wiring: https://deskthority.net/download/file.php?id=14967&sid=c68c17481081f474fb4a2c1e9b43a98d it seems like 1 wrap could fit around the pin.

Also, how would direct wiring of the switches look like? Most boards (and tutorials) use a matrix, and the few direct wired boards I could find use a PCB instead of hand-wiring. Would one pin of the switch be connected to a dedicated GPIO pin and the other pin connected to the next switch and at the end to GND? Like so:

[attachimg=1]

Cheers

Title: Re: Sturdy solderless board with wire-wrap tool possible?
Post by: Leslieann on Thu, 10 September 2020, 21:58:33

Absolutely not.
Besides questionable connections (the original use was for something not being pounded on), the pins on the switches are not strong enough or designed for this sort of thing too short, wrong shape, no strength.

Title: Re: Sturdy solderless board with wire-wrap tool possible?
Post by: coniurare on Fri, 11 September 2020, 07:44:24

Hey, thanks for the answer. I suspected as much thinking especially about the flat pin on the switch, good to get a confirmation. Got my hopes up when I found a picture of the ErgoHack keyboard today (but that's probably wrap + solder):

[attach=1]

Ignoring the wire-wrap: is my assumption about the direct wiring correct if no matrix is used?

Title: Re: Sturdy solderless board with wire-wrap tool possible?
Post by: jamster on Fri, 11 September 2020, 08:31:41

If you google for images of some if the 3D DIY keyboards, you will find photos of point to point wiring. Try looking for Dactyl Manuform wiring.

Title: Re: Sturdy solderless board with wire-wrap tool possible?
Post by: coniurare on Fri, 11 September 2020, 12:37:03

Yeah, I tried that before posting but all I could find was matrix layouts, even when searching only specific sites like geekhack, imgur or reddit (e.g [search term] site:reddit.com etc.). Could of course be that I overlooked them or my search engine fu is just bad.

After looking for macropads on /r/MechanicalKeyboards in the hope that they are more likely to be direct wired due to the few keys, I found one (most had a PCB, haha...):

[attach=1]

https://old.reddit.com/r/MechanicalKeyboards/comments/8serhg/minimacro_4_button_macropad_driven_by_attiny85/