Good thread Dave!
I agree with you. Discomforts come (mostly) with age and we all have a ways to deal with them.
The nut cracker is a great idea, If you're afraid to damage metal caps, you could line the surfaces of the nutcracker with strips of rubber from an old inside bicycle tire tube.
My biggest discomforts are arthritis in the hands and my poor eye-sight.
To hold a part firmly down to my cutting mat to keep it in place while I cut or sand it, can be painful at times, and sometimes my joints lock, especially in the summer with high humidity. The only thing that helps is to give it a rest for a while.
I wear -3 lenses and use +2.5 reading glasses. To get a better look closer by I also use 2 pair of reading glass at the same time. (I got this from the clockmaker Steve in the BBC series 'The repair shop'). Looks silly, but it works.
I've tried head magnifiers, but my head is big enough as it is. No, just kidding. I tried them, but they just don't work for me.
A while back I got a really priceless birthday present: a loupe-light with 84 leds and an 178 mm 5x magnifying lens.
Whenever I can I make and use templates and jigs to produce parts that are supposed to have the same form or shape.
The rib jig I made really helps to get the ribs straight and evenly spaced. Even for a one-off it pays off. Because of the arthritis, it is hard for me to keep my hands steady. Now I can rest my hands on both sides of the jig on the table. This way I can position the ribs more easy in line with the pencil lines.
Last but not least I use this precision ruler. It has holes for every 0,25 mm and it helps me to measure very accurately. You can use a sharp tipped pencil, a mechanical pencil or even the tip of a sharp no. 11 knife blade to pin-point reference points. Again I can work more precisely than with an ordinary ruler and trembling arthritis hands.
There is also one in inches.
Cheers,
Willem