WOW!
You are not kidding about modding the bottom keys! Initially seems very extreme, but I can see how it potentially could have a large beneficial effect (I do not have a Datahand, but used one about 5 years ago).
I'm glad someone else likes the Ergonomic Touchpad, no one seems to know about it.
Thank you for pics and info on different tab lengths (mentioned in another thread).
After thinking more about your comment that my modification of the center (down) key looked extreme, I wanted to say more about the issues involved. With the factory design, fingernails need to be short enough not to get in the way. Theoretically, people could activate the switches with their fingernails, but that would limit the tactility. The north switch (in each key-well) which is designed to be activated by the fingernail can be felt through the fingernail, but in general, the attempt to operate the down switch and the side switches with long fingernails could be less satisfactory, though I would be interested to know if some lady somewhere is making it work. Apart from that, I think that DataHand Systems could have worked harder to accommodate the needs of women who do not want to cut their finger nails as short as men do.
The point of my modification is improve the ability of the fingers to home to the center of the key well and to be able to constantly orient themselves in center of the key-well. This could also be accomplished by making a small bump or dimple in the center of the center key (using the factory design), but that would not fix the other issue resulting from the ridge at the outer edge of the key. That is like a jump the finger must cross on the way to the perimeter keys. It is too close to the perimeter keys to be helpfully orienting to the fingers as they attempt to home to the center of the key-wells. By cutting the center keys down as much as I have, I allow for somewhat longer fingernails, and that can have a benefit in improving operator leverage or reach to the north keys, but if the fingernails are longer, they could also catch on the center key when the fingers are moving to operate the south keys. If the diameter of the center key is larger than I have made it on my modification, this catching could be more likely depending on the diameter of the operator’s fingers.
The objective is to allow fast movement among the five keys while also allowing the fingers to maintain a clear reference point in the center of the key-well. The center key needs to be big enough to be comfortable to operate the key and not so big that the fingernails of the operator might catch on the center key when the fingers make a southward movement. I have not experimented with different sizes of center key. I just did what I did about a decade ago and found that it achieved what I wanted to achieve.
Nonetheless, I can see the size of the center key is related to the size of the operator’s fingers. A person with very slender fingers might find their fingernails could catch on even a center switch the size of mine. It is not a problem for me, but I have not studied the idea in relation to other operators. For me, the arrangement accomplishes the greater efficiency I consider important---even if my fingernails get a bit long for the male standard. I have average sized hands for a man and average sized fingers or maybe smaller than average.
The center key is a comfortable size for me to operate, and I have now a decade of experience with it, sometimes working 18 hours. If this size was too small to be comfortable I would know it by now. This discussion might seem a bit arcane, but in my opinion it is central to the effective and most efficient use of the DataHand keyboard.
In addition, I find that I can keep visual track of the amount of dirt and dander in the key-wells and blow them out more easily with a can of compressed air. This is important, because the infrared light beam in each switch can be blocked if dirt or dander get in its path. That can cause the switch to stop functioning or to operate erratically. It is important to keep the key-well clean, but with the factory design, people cannot see how much junk may have accumulated under the center key until it has built up excessively. Normally, they do not do periodic maintenance until a switch starts to malfunction. In my design, the need to do a cleaning can be seen without waiting for a blockage to occur. Most of the accumulation in the key-wells is from the fingers themselves. At least, in my case, other foreign matter is not a problem so much as the dander that flakes off of my fingers.
This brings me to another matter I am thinking to address for your benefit inasmuch as I see you are a Colemak user. I use the Dvorak layout on the DataHand keyboard, and I have from the beginning, because I learned the Dvorak layout on the flat keyboard about seven years before I got my first DataHand keyboard in 1992. In the beginning, I used standard conversion software to make the change, but in 1998, DataHand Systems offered their own version of Dvorak, and it is better. It is optimized for the DataHand keyboard design. In addition, it improves on DataHand QWERTY by improving the functionality of the Arrow keys. They are placed on the right pinky in the NAS mode. Thus, by holding down the thumb on that hand, the little finger can quickly be used to navigate. I use this feature to avoid having to use the mouse. I estimate that this saves me from using the mouse about 30% of the time, maybe more. It is very fast, because there is no hand movement to get to the Arrow keys (as on the flat keyboard).
I mention this, because you might want to get DataHand Dvorak and convert it to Colemac with a software package like Ukelele (which I have not tried to use on a DataHand keyboard, so I do not know how it would work). On DataHand QWERTY the Arrow keys are in the Mouse mode, and they require a more awkward double shift. I think DataHand Systems should give DataHand QWERTY users the same functionality they have given to DataHand Dvorak users, but they have not done it. They could have made the change 12 years ago when the idea was installed on DataHand Dvorak, but they did not. DataHand QWERTY users do not know about this feature, so they do not demand it.
To me, one of the best features of Colemak is the swapping of the Backspace and the Shift Lock keys, but on the DataHand layout that is not needed, because the Backspace key is already in a very convenient place. If there are any keys to use less on the DataHand keyboard, it is the north keys, because the fingernail activation of keys is the most awkward movement for most people. After people get used to it, it is not so awkward, but with QWERTY, 50% of the work is on the north row. I would rather concentrate more of the work on the center and south rows, and both Dvorak and Colemak do that better than QWERTY does.
Dvorak puts about 70% of the work on the center row, and I think Colemak does similarly. The Blickensderfer DHIATENSOR layout would probably be the best layout on the DataHand keyboard, but it took me until last year to figure that out. It puts 70% of the work on the south row on the flat keyboard and more than 95% of the work on the south and center rows plus four side keys on the DataHand keyboard. That leaves very little work to be done by the fingernails. I hope this will be a helpful expansion of the discussion.
Finally, thanks for the helpful information on the trackpad enhancement software. That gives me a bunch of studying to do.
