Taig lathe speed reduction, done two or three years ago. Everyone figures out their own way to do this. The steel pulley on the rear of the headstock probably doubled the weight of the lathe. The hardened steel shaft in the bronze bushings shows little sign of wear after quite a bit of use (for a taig anyway). I only use the bottom four speeds now; roughly 200 RPM at the slowest. I haven't experimented with parting tool types, but 25 FPM is roughly the fastest it can part without chattering the doors off the house. I made this modification to the taig while I was working in a production CNC shop, where we parted at a sane 400 FPM. It's not a fair comparison, but you know there were some sighs.
Aluminum base for the Taig lathe:
Rope winding machine I made when I was eleven or so:
I really wanted to have a sewn seam on this envelope design somewhere. The backside of a machine-sewn seam on paper is not a pretty sight, so I came up with a method to hide it. The seam is functional; it uses no glue there.