inconsistent threading

[yuuahmad]

does anyone here know how to solve this problem? is it using backlash compensation? or does my machine need to be dialed back? or is there a firmware setting that I need to change?

i am using the latest version of grblhal now

my scenario

• my lathe has a backlash of 0.1mm
• threading using G97
• backlash compensation on $160 I turn it off (value is 0)

here I attach a picture and diagram of my problem if there is any incomplete information just write it in the comments column.

[terjeio]

Backlash should not be an issue since threading is in one direction?
Which driver/board are you using?
Have you tuned the PID parameters with good results?
Spindle is relatively stable RPM-vise when threading?
What kind of encoder are you using? Number of of pulses per rev?