The desire for the Beagle with me was originally that with LinuxCNC and a quadrature encoder on the spindle along with the hardware QEP handled by the PRU we'd have an awesome little lathe controller. Alas, that's the one thing in MachineKit that hasn't been addressed yet.
Mach3 and my ELS both use one pulse per revolution for threading. And before this starts a massive thread on how that just can't work, it does work and as long as the spindle is reasonably steady it works well. But you obviously can't just stop the spindle mid thread and then turn the spindle by hand manually. So there are limitations. Doesn't prevent people from threading on either MACH or using my ELS. But, a 1000 line quadrature encoder on the spindle tightly coupled to the leadscrew with a ball screw nut on the carriage does make it possible to wind the spindle with a manual crank at 1 RPM and thread. That would be cool. I wasn't able to run a basic interrupt routine any faster than 20kHz which again for stepper motors and 1PPR was adequate but then I had a 40Mhz 8 bit PIC. Now I'd use at a minimum a dsPIC or even the PIC32 with the Quadrature encoder support. But I thought why bother, since MachineKit is LinuxCNC and can thread on a lathe. But not yet... John > -----Original Message----- > From: andy pugh [mailto:bodge...@gmail.com] > Sent: October-13-17 3:02 PM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] MachineKit on the BeagleBone Black > > On Thu, Oct 12, 2017 at 9:02 AM, Martin Dobbins <tu...@hotmail.com> > wrote: > > >> My guess is that Path pilot is probably easier to use than Mach 3 or Mach > >> 4 and easier for Tormach to support which is why they made the decision to > >> move away from their previous software offerings > > I think it was because they wanted to make a lathe, and Mach has never > been better than "OK" for lathes. > It basically doesn't do spindle-synched motion as well as LinuxCNC. I > suspect (but don't know) that the Mach motion-controller doesn't run > in realtime so has to predict rather than react to the spindle > encoder. > > > I don't know the facts, > > I know some of them, Tormach came to one of the LinuxCNC-fests in Wichita. > > -- > atp > "A motorcycle is a bicycle with a pandemonium attachment and is > designed for the especial use of mechanical geniuses, daredevils and > lunatics." > � George Fitch, Atlanta Constitution Newspaper, 1916 > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
