Aer's 60% Model M Project

[Aer Fixus]

So, since I won't be completing this for a while, I thought I'd post the progress I've made. My current hang up is conductive paste. I'd like to find a conductive paste that actually works correctly with the Model M's traces so I can reinforce some of the copper tape that just wouldn't make contact or would separate after some time. Some of them are just being stubborn, but most of the connections work fine and I've even tested them with keys and the ones that make contact work great!

The project went fairly well until a couple of the connections became flaky and the conductive paint I used didn't work at all. I'll probably buy a silver based conductive paint that others have used to touch up Model M membranes and use that. It just needs to connect the wafer thin mint. I mean paper thin gap.

Also note that I added two meta keys. This project was started back when the Kishsaver was just a legend and no one but Kishy had one. I had no plans or expectations to get one. When I did the project hit a wall because, why did I need the 60% project when I had what I wanted? And in Model F form? Anyway, the goal of the project was to both mimic the Kishsaver and create an ultra-portable buckling spring board with the footprint of a Poker II (or similar 60%). And so far, I've succeded, minus the obvious snags.

To complete this project, I need a conductive paste that works with the Model M membrane. I'll also need a custom controller (and it will likely be teensy based). The original idea for the controller was to use IBM's controller for PS2 compatibility and have a detachable numpad for if I ever wanted a numpad. I've basically ditched the numpad, but i still have all the parts if I wanted to make it some day. I also need some sort of enclosure, but I've got access to 3D printers and a mini CNC mill that should be able make something spiffy.

So here it is (view the full album for a couple extra photos http://imgur.com/a/4PzTP):








P.S. Ignore the rotation/distortion of the last two images until imgur decides it want to rotate them like I asked it to...

Edit: Aha! Post 222!

[rowdy]

An interesting project!

Given the scarcity of Kishsavers, this could turn out to be fruitful anyway.

[TheMamaMafia]

I got a similar project going on! However I'm using the keyboard from an old ActionWriter for this, but especially the part about the membrane already have helped me a bit. Thanks!

[Skechup]

The membrane idea is pretty neat. Repairing membranes are pretty difficult but doing it like that seems like a simple way to go about it. But personally, I would have the copper squares a little smaller to fit the membrane better and to make it prettier overall.

[zombimuncha]

future KOTM winner here.

[nubbinator]

Definitely interested to see where this goes, particularly the case.

[Aer Fixus]

The membrane idea is pretty neat. Repairing membranes are pretty difficult but doing it like that seems like a simple way to go about it. But personally, I would have the copper squares a little smaller to fit the membrane better and to make it prettier overall.

Originally, I expected the copper tape to be enough on it's own, so I made them larger to cover a little more of the traces. Now that I know I need conductive paste anyway, I'd make them smaller next time. I also made them wider than necessary because it was first run and I didn't want them ripping when I inevitably took it apart and put it back together over and over. And, it won't really matter in the end because the case should cover them up.

If I were to do this again, they would be a bit smaller.

[neverused]

As crazy as this sounds, is it possible to scrape these traces and solder to them with something like kynar or magnet wire?

[Aer Fixus]

As crazy as this sounds, is it possible to scrape these traces and solder to them with something like kynar or magnet wire?

I don't know, actually. I'd imagine it would be incredibly hard if not outright impossible. I'd imagine that biggest concern would be the heat deforming the plastic. And I don't imagine the existing traces have enough metal content to hold the solder, but I could be wrong. I might try it for fun at some point in the future just for the knowledge of what happens.

Another more direct method could be to use conductive paste touching the wire and the trace. That would work, although I'd be concerned with the wire pulling out because the paste wouldn't act as a glue (because it's not really meant to be and it already has a hard time sticking to the plastic, which is why I'm using it in conjunction with the copper tape instead of alone). In addition, it would make assembly harder with attached wires going everywhere.