I prototyped a chisel handle with a 7° tri-oval camber and a carbon fiber core with TPU overmold to defeat bench-roll. At 6 pm during a glue-up, it found the single downhill vector off my 34" bench and torpedoed my shoe like it minored in physics out of spite. Anyone else design for ergonomics and discover gravity’s UI is undefeated?
Add a tiny flat facet on one camber; TPU’ll bite and kill that ‘single downhill vector.’ Sound workable?
On TPU, I’ve had better luck cutting a 1 mm groove and popping in a 2 mm silicone O-ring near the butt — acts like a speed bump even when “gravity’s UI” kicks in at 6 pm. Downside: you’ll feel the ring in a choked grip, so set it just behind your usual hand. Got a dog hole on that 34" edge to pair it with a tiny lanyard loop as a backup?
Stick a 3M Bumpon near the butt; clean TPU first or it peels — ‘gravity’s UI’ loses.
I had one that “torpedoed my shoe” too, and I fixed it by drilling a 5 mm off-center pocket in the end cap and epoxying in a steel slug so it settles heavy-side down and stops wandering. It adds a hair of tail weight, but you don’t feel it in use — want the offset and depth I used?
Add a 10 mm flat at the ferrule on the ‘7° tri-oval’ facet — mine stopped at 6 pm; minor grip tradeoff.