The issue I see is how to machine this so that it fits "perfectly" so as to have zero backlash.
An alternative might be to have three sets of planetary gears with some sort of spring loading so as to take out the "slop." Ken On Thu, Dec 21, 2017 at 5:21 AM, Gene Heskett <[email protected]> wrote: > On Thursday 21 December 2017 04:47:46 Roland Jollivet wrote: > > > The video shows only one planetary gear, which is obviously two gears, > > stacked. > > > > Can there be three planetary gears, maybe each with a different > > top/bottom offset? > > I can't figure out if it would work, or just jam up? > > > I think 3 gears at 120 degrees on the planetary yoke arms would work just > fine. It would require assembling it so each planetary is in time with > the offset the moving ring has at that point. Possibly a bit tricky, but > once in time should just stay in time. > > > > > > On 21 December 2017 at 11:18, Chris Albertson > > <[email protected]> > > > > wrote: > > > To make this really work for rotary tables you need a very fine > > > pitch. I have seen these 3D printed in plastic but they slip and > > > don't handle much torque because the outer ring deforms > > > One idea I had was to press fit the plastic ring gear into a short > > > section of steel pipe. > > > > > > Put you can buy these drives already made for about $250. That is > > > really not abad price for arc-second level precision and near zero > > > backlash. > > > > > > On Wed, Dec 20, 2017 at 10:15 PM, Lawrence Glaister <[email protected]> > wrote: > > > > very cool Gene.... had some troubles playing the video, but I seem > > > > to > > > > > > have > > > > > > > the gist of it. It does seem like a very interesting design for > > > > rotary tables.... just have to figure out how to re-purpose some > > > > rear end ring gears and pinions.... hmmm... was thinking of > > > > regearing the jeep anyway!. Lawrence Glaister VE7IT > > > > > > > > On 2017-12-20 07:36 PM, Gene Heskett wrote: > > > >> On Wednesday 20 December 2017 15:06:20 Gene Heskett wrote: > > > >> > > > >> On Wednesday 20 December 2017 12:36:57 [email protected] wrote: > > > >>>> I got my first prototype working. It came out to be 60:1. > > > >>>> sun = 15 > > > >>>> first planet = 15 > > > >>>> first ring = 45 > > > >>>> second planet = 14 > > > >>>> second ring = 45 > > > >>>> I have a short video but can not post it here > > > >>> > > > >>> Need more details plz. Like did you make or source the gears > > > >>> etc. And there's lots of places on the net to put a video, even > > > >>> my site (see sig) is available if you send it to me via a pm. > > > >>> I'll figure where to put it and make a link. Biggest problem is > > > >>> my upload back to the viewer is only about 2.5 Mbits/Sec. So > > > >>> playback may stumble. But at least it will be out there... > > > >>> > > > >>> Cheers, Gene Heskett > > > >> > > > >> Grumpy's video is now on my site in the sig, with a link from the > > > >> front page. Enjoy. Sure, its only plywood, but it works as a > > > >> proof of concept. I may see if I can make one in steel, with > > > >> bearings. In wood, its certainly compact compared to a worm and > > > >> eccentric bull gear. > > > >> > > > >> > > > >> Cheers, Gene Heskett > > > > > > > > ------------------------------------------------------------ > > > > ------------------ > > > > 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 > > > > [email protected] > > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > -- > > > > > > Chris Albertson > > > Redondo Beach, California > > > ------------------------------------------------------------ > > > ------------------ > > > 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 > > > [email protected] > > > 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 > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > 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) > Genes Web page <http://geneslinuxbox.net:6309/gene> > > ------------------------------------------------------------ > ------------------ > 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 > [email protected] > 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
