Quote Originally Posted by JAZZCNC View Post
555 timer hasn't been ruled out but I would have to have the single step option like the detent of the MPG.
How about a hybrid system, keep the MPG for fine control but have a button that also injects pulses from a (variable frequency) 555 timer type circuit? Direction is set by the wheel and that is used for fine adjustments but for rapid traverse, the button is used.