Re: [CAD_CAM_EDM_DRO] EMC Lathe mode.

Doug Fortune wrote:

> "Art Fenerty" <fenerty@...> wrote:
>
> > Maybe I'm gonna have to add lathe mode to my ever growing list.
>
> Its already there with your existing software!
> Although the addition of threading and css (constant surface speed)
> spindle rpm control would be very nice.
>
> > Does anyone sell a simple optical sensor that sticks on a lathe
> > and pulses every time a painted dot or something passes it, that
> > should be all thats required shouldn't it?
>
> USDigital http://www.usdigital.com sells rotary TTL quadrature output
> encoders with an index channel. You could just use the index channel
> (one pulse/rev), but you'd only be able to do single-start threads
> accurately. It probably depends on your programming constraints,
> but probably want to use a course A/B encoder (say no more than
> 180-360 counts/rev) to guage your X&Z progress. More than that
> and it gets harder to keep up with the counts (at 2000-3000 spindle
> rpm).

Why is this? The computer doesn't have to count individual pulses.
Just every servo or stepper cycle, it needs to check the current count
and figure out where the X and Z axes need to be to stay in sync.

Jon