After 50 years of programming on a keyboard, my fingers have had it. I can't use my Unicomp without my knuckles hurting
Hi mps. Welcome to Geekhack! Hope you enjoy your stay, and I hope your pain improves.
First, I have a general recommendation regardless of keyboard, which might or might not apply to you:
See if you can find a way to type with your elbows, forearms, wrists, and palms “floating” in the air, not resting on any surface. If doing so puts strain on your shoulders or upper arm muscles, try to bring the keyboard closer to your body until you can type with your upper arms hanging loosely at your sides with your back and shoulders relaxed, and tilt the keyboard such that the top surface is parallel to your forearms. If you aren’t resting your arms on an armrest/table/palmrest, then when you type any impact shock can be transferred from your fingers to the strong muscles in your upper arms. By contrast, if you are using a palmrest, then your hand will be static, leaving all shock to be absorbed in your finger joints.
As a corollary, try to type with an airy, springy, “dancing” style. Instead of mashing your fingers down with every keystroke, try to just use the minimum force you can to get past the click point, but no more. A Model M is actually pretty good for this, because the spring buckling is very dramatically tactile and loud. The biggest source of shock to the finger joints is from hitting the bottom of the stroke with a hard impact, rather than from the rest of the keystroke. If the keys were just too hard to press, but you were typing without mashing them more than necessary, I suspect you’d be feeling tired rather than in pain. [Hard to be sure about this without watching you type directly.]
It probably goes without saying, but getting good sleep, exercise, and diet, avoiding chronic anxiety, and taking a break from the computer to walk around a bit every hour or so, with shorter breaks from continuous typing a few times an hour, can also help a lot.
Second, I echo Findecanor’s suggestion to try a split keyboard with some hand separation and/or aggressive tenting, such as a Matias ErgoPro (if you want something easy to learn) or a Kinesis Advantage. Reducing the amount of wrist pronation required to type makes a big improvement to typing comfort, because it gives you a lot more slack to work with in all of the rest of your posture choices. A standard keyboard is not very well designed to match the human body, and forces you to make some trade-off about where to distribute static strain between your shoulders, your arms, or your wrists. A well designed split keyboard lets you reduce the overall amount of static strain quite considerably.
Third, as to your specific comment about typing on a Unicomp being too much, note that IBM/Lexmark/Unicomp Model Ms are quite stiff switches. Many other switches use dramatically less force. I agree with Chyros that SMK clicky switches are really nice (these are sometimes called “Monterey” switches because they were used on a particular keyboard sold by Monterey). If you want a standard one-piece keyboard, they might be a good alternative to a Model M for you. They’re clicky enough to feel familiar to a Model M user, but take substantially less work to press, which should help you to type lightly.
A Model F is also notably less stiff than a Model M (though still stiffer than other alternatives), if you decide you can’t give buckling springs up.
Other possible alternatives include clicky “space invader” switches from a mid-1990s NMB RightTouch keyboard, clicky Alps, or even (though not my favorite) clicky blue Cherry MX switches. MX blue switches are much less tactile than a Model M, but take substantially less force to actuate.
If you have RSI or similar, definitely a tactile switch is not the way to go (click/bump provides a slight increase in pressure as it happens), so linears are a good choice.
Speaking for myself, I can’t agree with this advice, though the scientific literature is pretty spotty on this general subject, so this is more of a personal intuition than a validated general fact.
Tactile switches are a big help for typing lightly, because they give you a direct signal when you’ve actuated the switch, which reduces finger force at bottom-out.
If you get a linear switch, I recommend something with a high actuation point and a beeper for direct audio feedback.
