Based on the videos and your descriptions of the behavior, you may be running into a TP issue I've seen (in simulation) with very sluggish spindles or very high spindle speeds. Here's what I think is going on:
1. The rigid tapping cycle allows a hard-coded 10 revolutions <https://github.com/LinuxCNC/linuxcnc/blob/master/src/emc/tp/tc.c#L856> of overtravel beyond the nominal bottom of the hole when reversing direction. 2. The spindle starts reversing direction only after the Z axis has reached the bottom, so the spindle has to be able to stop in 10 revolutions to stay within the budgeted overtravel. 3. If the TP hits the end of the overtravel, it prematurely declares the motion to be complete and stops following the spindle motion. Do you still see this behavior if you run the spindle slower? Your spindle seems to take a long time to reverse, so at high speeds you may be hitting this limit. Best, Rob <https://github.com/LinuxCNC/linuxcnc/blob/master/src/emc/tp/tc.c#L856> On Tue, Jul 21, 2020 at 11:18 AM Matthew Herd <herd.m...@gmail.com> wrote: > Ahh, so I do use limit switches and a homing routine. So it’s homing to > the same position (plus or minus a few thousandths or so). > > > On Jul 21, 2020, at 11:07 AM, Jon Elson <el...@pico-systems.com> wrote: > > > > On 07/21/2020 04:20 AM, andy pugh wrote: > >> On Tue, 21 Jul 2020 at 10:18, andy pugh <bodge...@gmail.com> wrote: > >> > >>> We are not looking for noise, we are looking for spurious encoder > count resets. > >> But, thinking further, even if there _is_ noise on the index line, the > >> encoder counter should ignore it. It ignores all the _real_ indexes > >> unless index-enable is set true in HAL. > >> > > Yes, the only thing I can think of is he's hitting his soft limits. Over > time, starting and stopping LinuxCNC, > > without homing, the machine limits will drift. If you have rational > limits in the .ini file, you will eventually reach the end of them and have > really strange behavior. it can be fixed by homing in a safe position, > > but best to put in home switches and actually home the machine to a > repeatable position every time. > > > > Jon > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
