Thanks Gene My emco is running a pi 4 as well. Model b, 4gb. What kind of latency figures are you getting on your servo thread? I find mine to be a bit finicky unless I keep wifi off
Phil T. The Feral Engineer Check out my LinuxCNC tutorials, machine builds and other antics at www.youtube.com/c/theferalengineer On Fri, Mar 5, 2021, 7:56 PM Gene Heskett <[email protected]> wrote: > On Friday 05 March 2021 18:35:19 andy pugh wrote: > > > On Fri, 5 Mar 2021 at 23:31, Feral Engineer > <[email protected]> wrote: > > > Can someone send me a copypasta of their spindle hal stuff? Pid, > > > ff0,1,2 encoder feedback, all that? > > > > I don't actually run PID on my lathe spindle. I have some moderately > > complex gear selection stuff going on, but otherwise I just trust the > > VFD to do the job. > I don't have a pid loaded in either of my machines that are running a > vfd. The vfd is stiff enough it doesn't need fawncy controls. > > The only reason I have an encoder on the sheldon lathe is for G33.1 and > G76 support. Both of those slave the z travel to the spindle, what ever > its running at doesn't change more than 2% under cutting load for G76, > and maybe 5% for a big tap doing rigid taping. G76 also slaves the x to > the programmed G76 cutting depth. On the sheldon, a pwmgen feeds a > spinx1 which controls the vfd. Not even an d/a except the spinx1 because > I run the pwmgen at a rate thats above the bandwidth of the spinx1. > > You get far better results by properly tuning the vfd. OOTB they suck > huge dead toads thru soda straws. With a pwmgen getting the speed > signals from motions spindle output, that pwm fed to the spinx1 along > with the dir signal, and a bit of hal sequencing, my Sheldon, turning at > 100 revs in high backgear, and low belt position/speed, I can do a rigid > tap move, and measuring the overshoot at the bottom of the G33.1 move, > is .25 turns. That's with a nearly 40 lb 8" 4 jaw chuck mounted. Who > needs a pid? > > That .hal file is attached. Cherry pick with my blessing. Sure its a > rpi4 file, but its running a Sheldon lathe that after stripping the > stuff linuxcnc doesn't need, and putting in decent ball screws, > still weighs around 1350 lbs. > > Stay safe and well, John. > > Cheers, Gene Heskett > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > If we desire respect for the law, we must first make the law respectable. > - Louis D. Brandeis > Genes Web page <http://geneslinuxbox.net:6309/gene> > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
