G-code provides for sophisticated CAM programs to directly control feed rate for
non-Cartesian motion (rotary axes) by specifying the Time to complete the move
instead of the Feed rate. The code for this mode is G93 and the Rate is specified
as a number equal to 1 divided by the desired time to complete in minutes. This is
called "Inverse Time Mode".
While in G93 mode, every block that contains feed motion must have an F word,
I.E. feed rate is not modal while in G93 mode. For a simple rotary axis this places the
responsibility for compensating for Z radius effects on tool tip travel as the A axis
turns on the CAM program generating the code. It also allows for much more
complicated situations than just a simple rotary axis. The Mach3 software did
have a mode that would work fairly well for a simple rotary axis, but it was not
industry standard and is not implemented in Mach4.
Steve Stallings
PMDX
django013,
I have tested many CAM programs in the past.
I do not know of any CAM program that can output surface speed and the A Axis using the Z Axis as the radius to control the speed.
If you want a controller that can in all conditions you need to speed the $$, HiCON cards can do it all.
Regards,
Mauri.