Self-locking keeps tools like screw jacks from unwinding under load. Acme Screw Thread Profile by Wizard191 CC-BY-SA 3.0 Screw thread profiles can be modified from the standard V profile for ...

The table is not all wood, of course; metal bushings and pins are used in the scissor mechanism, and the lift drive is a stout Acme-thread screw and nut. We’re impressed by [Marius]’ joinery ...