Nice work! The message you're getting in axis is a new feature I added. It warns you if the combination of spindle speed and thread pitch would require more than 90% of your maximum axis velocity. If so, it slows the spindle down to a safe maximum speed before starting the thread (in this case 230RPM). The 90% value is arbitrary, I just wanted to have some safety factor in there.
Comparing the two acceleration plots, it seems like the acceleration during the start of the thread is higher in stock 2.7 than with my branch/ The high initial acceleration is good, though, since it settles in about 120ms, whereas the new branch takes about 200ms. I'll run the same program in simulation tomorrow and see if I can reproduce the effect. It may be worth trying the same comparison in G61 (in case blending is causing it). Best, Rob On Fri, Nov 25, 2016 at 8:37 PM sam sokolik <[email protected]> wrote: > ok - I finally did some testing on the emco using this branch.. > > > https://github.com/robEllenberg/linuxcnc-mirror/commits/feature/nominal-vel-during-sync > > This is a thread using this program > http://electronicsam.com/images/KandT/testing/robthreading/test.ngc > > This is the current 2.7 behavior > http://electronicsam.com/images/KandT/testing/robthreading/current.png > > This is with robs fixes > http://electronicsam.com/images/KandT/testing/robthreading/robnew1.png > > It looks like the acceleration spike are defiantly smaller. > > I did find an oddity on both branches - quite often it seemed to > overshoot initially and then slow back down. I don't know if it is an > artifact of my config (100 line single channel encoder + index. never > seemed to effect the threading I have done. > > http://electronicsam.com/images/KandT/testing/robthreading/current1.png > http://electronicsam.com/images/KandT/testing/robthreading/robnew.png > > Also - rob - it prints in axis every pass velocity at line 8 is 230rpm > or such.. (paraphrasing..) > > sam > > > On 09/25/2016 07:47 AM, Robert Ellenberg wrote: > > Hi All, > > > > Recently, I found a way to reduce the acceleration / velocity jitter > during > > threading and tapping motions (see this issue on github > > <https://github.com/LinuxCNC/linuxcnc/issues/164> and the > > feature/spindle-sync-jiiter-fix branch > > < > https://github.com/robEllenberg/linuxcnc-mirror/tree/feature/spindle-sync-jitter-fix > >). > > The effect looks significant on the HALscope, but I'm not sure how much > of > > a difference it would make on a real machine. Is anyone interested in > doing > > a before and after test on real hardware? > > > > Thanks! > > Rob > > > ------------------------------------------------------------------------------ > > _______________________________________________ > > Emc-developers mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-developers > > > > > > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers > ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
