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jaredjOPDactyl Manuform, Keebio Fourier•

I learned that the shape of the Dactyl/Manuform keywell is not magically ergonomic for everyone, and embarked on a seemingly interminable series of tweaks and printed mockups. This one has different radii for each finger's column, and the columns are splayed, i.e. angled away from each other. It's been some 20 iterations of tweaking and printing mockups of the keys. Now I've printed this frame and minimum viable bottom out, attached switches and (random) caps, and it's revealed a fresh set of issues. Several keycaps collide with each other. The outermost thumb keys are probably not going to be usable. And while the four inner finger key columns seem more comfortable, the two outer columns for the index and little finger seem harder to reach.

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autocorrelation•

Although an extreme measure, you can work-around the collision issue by shaving down the edges of the keycaps and even switches themselves. That's what I noticed the person who made the ErgoWarp had to do get the extreme curvature in some iterations. See the pics for "Clipped1" and "Clipped2" here.

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jaredjOPDactyl Manuform, Keebio Fourier•

Yeah - the more I mess around with the key placement, the more I think I'm reaching for a local maximum, because I haven't made a wider survey of key placements, of which the ErgoWarp would be an important part.

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jaredjOPDactyl Manuform, Keebio Fourier•

btw the code behind this print is https://github.com/jaredjennings/dactyl-keyboard/tree/70c0b73fe7e3e8306dea5e6e4dcc683ea95ea438

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jasonmfry•

Oh nice! What’s the tent? I have mine pretty extreme, probably 45 degrees, and I want a dactyl manuform :D

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jaredjOPDactyl Manuform, Keebio Fourier•

Yep, it's 45 degrees. So far what I've learned about that from having a frame with switches and caps is that if there is not some kind of serious non-slip on the bottom, it's insufferable. Of course, I learned the same thing pretty quick about this stock Dactyl Manuform I'm typing on now...

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new_ion•

I found that pi/7 (or 5, can't remember even when looking at my code) with a row curvature of 40 is the tightest you can get without keycaps touching on a 5x6 with DSA caps.

Anti-slip can be dealt with by dollar store drawer liner.

Use the "test" output to see the keycaps colliding, works pretty well for DSA.

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henrebotha•

What is row curvature?

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new_ion•

The "dishing" across the breadth of your hand. If you open the code, it's the alpha term.

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jaredjOPDactyl Manuform, Keebio Fourier•

I actually have a varying column curvature over the column: it is tighter for the closest keys and the farthest keys, making it sort of elliptical. On top of that is a cascading series of kluges which I applied based on looking at the keycaps rendered in OpenSCAD. But it's hard to see all the gaps because everything is curved.

Since printing this, I've done what I should have in the first place: added a view where the intersection of each keycap with each keycap adjacent to it is shown in a bold color. If anything is shown, it is bad. And there are intersections. Of course, the sa-cap shape is still pretty low fidelity.

But all these problems are because of the contortions I've put the key-place function through.

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Feoner8•

Love the tilt on this!

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sanjibukai•

Do you have pictures of the underside? They keys seem short.. What they are?

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jaredjOPDactyl Manuform, Keebio Fourier•

Here you go. https://imgur.com/a/n4WwB3p

The original Dactyl has a top and a bottom that screw together, and I kept that design. The thing with the towers is what I'm calling the "minimum viable bottom." I think next time it's only going to have three towers. This doesn't look how I want the case to look at all, but it holds up the frame, which is the piece I'm currently trying to get right.

The top-down picture probably shows best how much longer the middle-finger column is.

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sanjibukai•

Thanks for the details.

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jaredjOPDactyl Manuform, Keebio Fourier•

I don't right now. But surely I'll deliver. ;) The keycaps are DSA; the switches are random Kailh, Gateron, and Novelkeys sampler switches.

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BHRobots•

Very nice! I like the aggressive curvature. I've done a similar test print, and it just feels nice.

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BrewingHeavyWeather•

Oooh...I like the way you spaced out the columns, rather than cramming them all next to each other. I've been beginning to think I was one of the only people that find tight grids less than ideal (do most people have fingers that go out parallel to each other, or what?).

How well does the top row feel, with the keys not quite aligned for finger extension?

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jaredjOPDactyl Manuform, Keebio Fourier•

Columns: On my Dactyl Manuform, my index and little finger tend to rest toward the outside of their home-row keys - even sometimes half on one key and half on the next. I thought similarly to you: my fingers aren't parallel, why should my columns be? But on this prototype, while my index and little fingers rest properly on their respective home row keys, it means the second column is twice as far or more to reach. I haven't even tried It's not just tipping my finger one way or the other, like it is now.

I'm going to try tipping each key on the outside columns (rather than the entire column) inward, and if that doesn't work, I might actually ditch the splayed columns.

About the top row: the straighter your fingers are, the harder it is to push outward, and the easier it is to press down. I wanted to press the number row keys not poke them, so I tipped the number row outward from the bowl, so to speak.

I always aimed for 60% in my keywell keyboard not 40%, but I'm now on my second stopgap keyboard that's a 40%, and I'm not certain anymore that I want a number row. If I'm going to have one, it needs to be close. So I brought it as close as I could. It's quite possible that my fingers will trip over those keys on their way to the top letter row. I could ditch the number row. But I told myself I'd at least give it a chance - I haven't had a split keyboard with a number row yet.

The exact thing you see here will never be a full, working keyboard. It's only the right hand, it's not wired at all, the keycaps collided when installed, and so I'll have to make more changes before making a working keyboard shaped something like this. But the action of pressing the keys has made this prototype instructive in a way my previous mockups weren't. The mockups were just plastic stand-in keys (sa-cap in the code) arranged properly, with plastic underneath to hold them up, and the test criterion was merely whether I could easily touch the keytops.

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