I have been thinking about thread cutting on my lathe for some time but the gears work out really expensive (and almost as rare as dragons teeth for my drummond)
so I thought tonight about a electronic feed system, basically you would have a bolt on sensor for the main shaft and a motor for the feed screw.
the sensor would send pulses to a control circuit which would then send pulses to the feed motor (the same as a usual cnc feed)
so in effect you could just program the feed to give you whatever feed ratio you needed, no more being restricted to the gear available.
does such a system exist already, if so links please and what are your thoughts on how accurate it would be?