Update - Dog Clutch Removed

About a year or so after building and fitting the dog clutch, I finally removed it from the mini-lathe. Due to the small size of the components in the clutch itself, it had needed repair a couple of times in that period. Also in that period I'd found a much better way of threading. I now do almost all of my threading with the tool mounted upside-down in the tool-post and the lathe running backwards (don't do this if you have a threaded chuck mount). In this configuration, the tool is moving away from the headstock as it cuts and you have all the time you need to disengage the leadscrew when the tool has run off the end of the workpiece.