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

On 09/11/2010 03:05 AM, Tony Smith wrote:

> <snip>The sensor can pick up the difference between air & steel, if
> you're got a
> gear with big enough teeth, it can pick when it's moving. Not sure it'd
> work with the nut though.
>
> Tony
>

Tony, I was discussing the nut which tightens the collet on the cutting
tool. They tend to be pretty big or they have rectangular cuts (like an
ER collet nut) which appear to be sufficient. Units like the Allegro
ATS family are limited to 10,000 Hz operation (600,000 PPM, for a 6
pointed (sided) nut, 100,000 RPM), so make sure you have enough range
for what you want. Adding a through hole in the round part of an ER
type nut (note through BOTH sides for balance) will make 300,000 RPM
pretty easy and 100,000 RPM trivial with a divide by two counter at less
than 4 KHz input.