John11668
28-09-2021, 10:08 PM
I raised a query in general forum which got no takers so wonder if I needed to raise it in a specialised area and maybe expand upon my problem a bit .
So here is my lathe with to toolposts on the saddle
30497
I was having problems with saddle lifting / jamming (and missed steps ) when I used back tool configuration with cutting tools reversed and counterclockwise spindle.
I have resolved some of the lifting issues with higher voltage at the steppers which allowed me to tighten the gibbs a bit , but clearly better to use clockwise rotation and tools cutting forward taking away the tendency to lift ,
This mode allows me to do beautiful left hand threads but not Right hand unless I cut left to right , from the chuck towards Z+.
But if I use threading tool in the bottom position and spindle counter clockwise, (and in front tool mode) I have my cutting forces in the correct direction and can produce beautiful Right hand threads. Seems natural therefore to use back tool for turning down with reasonably heavy cuts, then go to threading in front tool mode . But how do I do this during execution of a program.
The front or back mode is called up in the Ini file and I cant see a way to change mode without restarting gmoccapy. Surely what I want to do is sensible enough whether for threading or even for parting off. No problems changing spindle direction. No problems specifying a tool offset for any of the front tools . but how do I change the direction of movement for the tools.
Is there a way to change from front to back tool mode mid cycle .
So here is my lathe with to toolposts on the saddle
30497
I was having problems with saddle lifting / jamming (and missed steps ) when I used back tool configuration with cutting tools reversed and counterclockwise spindle.
I have resolved some of the lifting issues with higher voltage at the steppers which allowed me to tighten the gibbs a bit , but clearly better to use clockwise rotation and tools cutting forward taking away the tendency to lift ,
This mode allows me to do beautiful left hand threads but not Right hand unless I cut left to right , from the chuck towards Z+.
But if I use threading tool in the bottom position and spindle counter clockwise, (and in front tool mode) I have my cutting forces in the correct direction and can produce beautiful Right hand threads. Seems natural therefore to use back tool for turning down with reasonably heavy cuts, then go to threading in front tool mode . But how do I do this during execution of a program.
The front or back mode is called up in the Ini file and I cant see a way to change mode without restarting gmoccapy. Surely what I want to do is sensible enough whether for threading or even for parting off. No problems changing spindle direction. No problems specifying a tool offset for any of the front tools . but how do I change the direction of movement for the tools.
Is there a way to change from front to back tool mode mid cycle .