Re: [CAD_CAM_EDM_DRO] Machine mounted Tachometer with Surface Meter Per minuteThis

Danny Miller wrote:

> Oh yeah there's also gonna be a limit to a Hall/gear tooth sensor
> response time. A decade counter to lower the pulse count won't fix
> this. If it's too fast, the sensor won't have time to fall after one
> tooth leaves before the next tooth rises and it can't find a pulse out
> of that. 30K RPM * 6 teeth in a collet= 180KHz.

That would be 180 thousand pulses per MINUTE, or 3000 Hz, not any problem
for such a sensor. Digi-Key has stock on the ATS617 gear tooth sensor,
they are out
of the similar ATS667 part that I used. I'm fairly
confident it would work on a collet nut. It would have to be REALLY
close to the
points, though, less than a mm spacing. You would almost certainly need
some kind
of scheme to hinge the sensor away during tool changes, then swing it
back accurately
when done.

Jon