Is concavity worth it? (featuring Dactyl Manuform)

[RandomUser145]

Hi,
I currently own Kinesis Freestyle 2 and I feel like I am ready to advance in the ergonomics and just like the idea of thumb clusters. I'm pretty sure here.
But I am not sure about concavity. Is it really worth it? Does it improve ergonomics? I'm asking especially because from what I have found, there is just few options:
- Kinesis Advantage 2 - I don't like the fixed split
- Kinesis Advantage 360 - I know about this one, pre-ordering will start at the end of December, but I believe they won't ship outside US, so I won't be able to get one
- Dactyl / Dactyl Manuform - it's pretty hard to get one prebuilt, especially Dactyl
- Scylla - I guess this one is also hard to get

With Advantage 2 and Dactyl / Dactyl Manuform I am also worried about the reach for the thumb clusters (looks like the farthest one might be big of a stretch). This does not seem to be problem with Scylla, but again ... not sure if I can get it easily prebuilt.

So my questions are:
- Is concavity worth it?
- How are the thumb clusters on Dactyl?
- Is Scylla worth checking out?

I'm not too much into building it myself. I definitely want split, tent and columnar layout.

[vvp]

It is worth it.
There is also K80CS.

[iaji]

- Is concavity worth it? i guess, i used to like it but now i don't really care anymore.
- How are the thumb clusters on Dactyl? which one? the original dactyl uses an almost identical placement of kinesis advantage. the manuform variant, it will get tiring for the inner muscle of the thumb (can't remember the name) after a while.
- Is Scylla worth checking out? it's basically a dactyl manuform 5x6 mini. so, the choice is yours.

though it's worth noting that the point of the dactyl keyboards is the parametricity which you should check to really fit to your hands.

[jamster]

Worth mentioning that Lolligagger on this forum seems to have very nicely produced Dactyl Manuforms up for sale on a regular basis.

There is a generator for Dactyl STL files at https://dactyl.siskam.link/ but you really need to own your own 3D printer (or have access to one) to make good use of this. I went through maybe 5 iterations before finding a layout that I liked. And that wasn't even fiddling around with the more esoteric parameters like degree of concavity. There are also thumb cluster options.

Edit: And I have no other opinions on the Dactyl... after printing a bunch of case tests, I got sidetracked into other things and never built one

[RandomUser145]

though it's worth noting that the point of the dactyl keyboards is the parametricity which you should check to really fit to your hands.

Not sure what you mean by 'parametricity'. Do you mean the different sizes (5x6, 6x6) or... ?

[dusan]

Here are some examples with some parameters set, including number of columns and rows:
https://dactyl.siskam.link/example

[kurplop]

I thought I might like a concave keyboard but after trying one I didn’t. For me, being able to tilt and splay the two halves to your preference was supremely important. Vertical columns and thumb clusters were nice as well as programmability.

Your question is very subjective; like asking what the best fitting shoe is. The best answer can only be found after trying on many pair. If you have specific physical needs, they may dictate your requirements. Best wishes on your search.

[macroxue]

We all know that row staggering (x-staggering) is unnatural and should be avoided. Some amount of column staggering (y-staggering) can be healthy because it takes care of differences in finger lengths, to some degree.

There is one more dimension of staggering, z-staggering, that I build all my boards with, so my fingers are at even more natural positions.. For example, [5,4,0,0,2,4] are the heights (in mm) of the six columns of the right split. With this, the boards are still quite compact and easily tentable. I think a keywell may not do much better than z-staggering.

A large thumb cluster can be too much burden to the thumb. The big one is not really that flexible and I've read others saying they only use two-ish of the thumb keys most of the time. (Caution, small sample size).

[OddField]

You might also like to have a look at Glove80
https://geekhack.org/index.php?topic=114881.msg3086876#msg3086876