I'm interested in running some experiments to see how precisely I can cut threads for a worm gear.
As I understand it, cutting a perfect thread helix would require perfect synchronisation between z-axis movement and spindle speed. Leadscrew, belt transmission and non-constant spindle speed all contribute errors to the cut helix, as does temperature, vibration, machine alignment etc.
It appears that EMC2 can sync threading with BOTH spindle encoder pulses and an index mark (there are several YouTube videos showing the lathe chuck being manually rotated and the tool moves in sync), resulting in more updates to the z-axis speed, and consequently finer sync during threading.
Mach3 accepts an index pulse, but can it use spindle encoder pulses like EMC2 to further improve sync with the z-axis for threading?
Richard