On 09/25/2016 05:47 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?
I added tapered threading to G76 to my local 2.7.6 branch. I had concerns that the transitions between up to three synchronized path sections might not be handled well. My tests with 1/8 NPT and .25-20 straight threads with end taper worked well, but these probably would tolerate some variation. The end tapers usually don't mate with anything. I wanted to see what HALscope might show at these path transitions, but I didn't see any velocity HALpins, off hand, on my Pico servo setup, and I haven't taken the time to go any further on this. I would like to, maybe in the coming week. I can look at your issue while I'm at it. http://www.wallacecompany.com/cnc_lathe/HNC/ http://www.wallacecompany.com/cnc_lathe/HNC/ (BTW, I had to repair this encoder. The local voltage regulator was going into thermal shutdown, but I could not find excess current going into the near or far end of the cable. It turned out that I had old tantalum capacitors on the voltage regulator input and output that were going bad. I replaced the regulator with a high current version and smoked a tantalum, therefore indicating the problem. Not the most elegant trouble shooting, but finally found the problem.) -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/ ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
