By total coincidence, I am doing the exact same thing. I just bought a 600 line optical encoder and now I'm attaching it directly to a motor. The purpose is to write and debug some control software. In this case, I REALLY DO WANT to run at the encoder's maximum rated speed of 5000 RPM, or else what is the point of the test?
BTW, this control software will run on the new Raspberry Pi "Pico" that is selling for $4 per unit. It is a surprisingly powerful computer at a price point close enough to "free" that it does not matter. (Few people would care much between paying $0 or paying $4.) I think this "Pico" should be able to run four motors and four encoders all at 5000 RPM. We shall see. On Fri, Jun 18, 2021 at 9:21 AM Stuart Stevenson <stus...@gmail.com> wrote: > Sounds like a good plan. Hopefully the testing won't involve high rpms so > the od not being perfectly concentric will not matter. The motor bearings > will handle it but maybe the encoder bearings won't be as robust. > > On Fri, Jun 18, 2021, 10:52 AM John Dammeyer <jo...@autoartisans.com> > wrote: > > > This isn't as much a LinuxCNC question but more of an approach to how to > > machine something. > > > > The attached photo shows a coupler from a 3/8" encoder to 14mm Servo > Motor > > so I can test on the bench the Pi4 closed loop encoder behavior. > > > > This one didn't turn out very well. I drilled all the way through and > > then used a reamer to bring it to 3/8". It's a firm sliding fit on the > > encoder shaft. Without removing it from the chuck I then drilled halfway > > to 13mm and then used a 14mm reamer to bring it to size, testing with the > > motor shaft. > > > > Problem was the reamer was slightly tapered at the front so it did a poor > > job. I finished it up with the boring tool but maybe a few thou too > > large. However the wobble seems much worse than that. > > > > I'm thinking the better approach would be to drill all the way through > > undersize 3/8" and then drill half way with 13mm. Then only use the > boring > > tool to bring the back half up to 3/8" and the front up to 14mm. This > way > > if the initial hole wasn't concentric with rotation the boring tool would > > ensure it is. > > > > Make sense? Or is there a better way? > > > > Thanks > > John > > > > _______________________________________________ > > 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 > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
