Tighten This Bolt In Any Direction You Want
5th January 2021
Both videos after the break are in Russian, but the video and auto generated subtitles are enough to get the main points across. The bolt is an M42 size with a 40 mm pitch, with grooves cut in both directions to allow left-handed and right-handed nuts to be threaded. The large pitch means that instead of a single continuous groove like a normal bolt, ten separate grooves need to be cut for each threading direction to cover the bolt surface. Since this was all machined on a manual lathe, a dial indicator was required to maintain accurate spacing. It took [Oleg] four painstaking attempts to get it right, but the end result looks very good. Instead of a fixed cutter, he used a trimming router mounted on a custom clamp.