CNC cutting sculpted keyboards

[jacobolus]

I’ve been playing around with cutting some holes for Alps switches on a CNC router. I’m starting with MDF, but once I get a few designs figured out I’ll use some nice hardwood, cut the other side of the wood so there’s space for hand wiring, and make a bottom case as well.

Anyway, there are a few things wrong with this prototype: I forgot to rotate the switches for the 1x1.5 keys, the dimensions are just slightly too tight so I had to whack the switches with a rubber mallet to get them into place, and I don’t think the overall design is quite right yet.

But it was still a useful morning, and I think the general idea will work pretty well.

Front view:


Top view:


Side view:


With one of the switches removed so you can see the hole:


With a switch in the hole:


I used a 1/8" end mill to cut everything, because that’s the only tool I currently have. Before I get to producing a usable keyboard, I’ll probably get some other tools to cut the bulk of the material out faster, and make the final shapes with a bit finer detail.

I’d also like to see if I can cut keycaps.

[dorkvader]

Great work!

I like how you're using alps switches for prototyping, so you can save the good Cherry switches for production. You even picked a keycap set from that awful alps integrated dome board that was redone for cherry keycaps so you wont have to change the colour.

So without a PCB, what will hold the switches to the MDF? is the cut-out just the right size? DO you plan to direct wire with the wires underneath providing the stability (ie soldered right up against the ends of those holes) ? or just not worry about the rock / wobble as this is a prototype. I was thinking you were worried about that somewhat otherwise you'd have gone with foam or similar.

[jacobolus]

So without a PCB, what will hold the switches to the MDF? is the cut-out just the right size?

That’s right, they’re so so tight currently that it takes hitting them with a rubber mallet to put the switches in. I’ll loosen up the dimensions a tiny bit in the future.

There is absolutely no wobble in the switch as a whole (though the slider wobbles a bit as with most Alps switches), these switches are as stable as anything I’ve ever tried, comparable to a Model F, and the walls are currently tight enough that a keycap pulls off without budging the switch at all.

DO you plan to direct wire with the wires underneath providing the stability (ie soldered right up against the ends of those holes)?

For the moment, I plan to just solder them loosely, but if I decide to make the holes slightly larger, it might be helpful to bend the pins over a tiny bit on the other side for additional stability.

[Matt3o]

I am the process of getting myself a CNC as well. What do you have? Any suggestion?

[jacobolus]

I’m using a ShopBot at the San Francisco TechShop. I’m not the guy to ask for suggestions; I’m a total novice.

Check out this guy’s page though: http://lcamtuf.coredump.cx/gcnc/

[jacobolus]

Pictures from another run today:

[Zekromtor]

I thought thumb buttons were supposed to be lower than rest, not higher.

[jacobolus]

I thought thumb buttons were supposed to be lower than rest, not higher.

According to who?

I think it’s possible to do better if the switches aren’t all oriented the same way, but if they are going to be, I find it easier if the thumb keys are a bit higher than the finger switches.

[Synnöve]

^I'd say the logic is when the hand and digits are in a relaxed position, and the palm is level, the end of the thumb is at a lower elevation than the tips of the other fingers. Therefore, the thumb will require more contortion from it's rest state if the thumb keys are level with the other keys, resulting in more stress on the digit.

...or at least that's my humble impression.

[jacobolus]

Try it. :-)

But note, my prototype hasn’t gotten to the stage of adding tenting yet, which will make a big difference.

(Also note: I think in a final version, I want to have the thumb keys on a different plane from the finger keys. The further away ones will be higher than the closer ones. I think maybe I should also try to emulate this even on a flat version... I’ll try that in the next iteration.)

[dorkvader]

I think having a "higher" thumb button is nice. I find it pretty easy to "tuck" and use that as my primary method of pressing "alt" some days.