20130
« on: February 18, 2009, 02:42:26 PM »
Yes pulse rate is determined by the encoder count, most encoders give you the line count, so for example an encoder that has 500 lines will be 2000 pulses for one revolution.
Yes the step multiplier is electronic gearing, if you have 4x then one pulse from Mach will be 4 as far as the drive is concerned, this allows you to get faster rapids from the parallel port than you would without the multiplier as 500 pulses from Mach would be 2000 as far as the drive is concerned. The downside of course is at slow speeds you will get cogging, how noticeable depends on the resolution. With a SmoothStepper however you dont have to worry about that as its pulse rate is max of 4MHz so keeping the multiplier at 1x will not be an issue. If you decide on the parallel port then probably best to stick to a 500 line encoder, if using the SmoothStepper then probably 2000 or 2500 line encoder would be best.
Spindle may need to reverse for a few reasons, often mills have backgears and although some like my Beaver mill have true gearboxes that will keep the spindle rotating in the same direction mills like my Bridgeport will reverse the spindle direction when in backgear so you need to be able to reverse the motor. Tapping also requires reversal of the spindle and at this point in time you will need a floating holder however in the future the SmoothStepper should support fully synced spindle/axis so true rigid tapping should be a possibility.
Hood