Friction and elasticity in the ring gear likely account for most of the difference. I would imagine that the elasticity in the gear would be a fairly strong impediment to motion. Though calculations seem to be too much trouble.
On Mon, Sep 13, 2021 at 2:00 PM Sam Sokolik <samco...@gmail.com> wrote: > I agree with the quick math I did yesterday... But again I have no info > on these steppers.. > > And yes - I think it is totally usable at 35 ft-lbs.. there is some > friction there also running the 'wave' generator... > > On Mon, Sep 13, 2021, 12:26 PM John Dammeyer <jo...@autoartisans.com> > wrote: > > > Nice update. > > My math works out as follows: > > 35 lb-ft is 35 * 12"/ft * 16 oz/lb = 6720 oz-in. > > You said the ratio is 100:1 so that means to get 6720 you only input 67.2 > > oz-in. That's about 1/3 of what you suspect your motor can do. > > > > Something is wrong with this picture then. Especially since you were > > effectively using static torque rather than the much lower torque when > the > > motor is turning at say 400 RPM. With micro-stepping you also get a > > reduction in full step torque because the max current is now 0.707 x full > > torque. And without closed loop encoder feedback you can quite easily > have > > to micro-step a number of times before you see physical motion. > > > > None of that matters other than that you have shown your mechanics can > > handle 35 lb-ft which is all in all pretty cool ! > > > > John > > > > > > > > > > > -----Original Message----- > > > From: Sam Sokolik [mailto:samco...@gmail.com] > > > Sent: September-12-21 5:50 PM > > > To: Enhanced Machine Controller (EMC) > > > Subject: [Emc-users] Minimally printed rotary. Initial torque testing.. > > > > > > Small update > > > > > > https://youtu.be/eW1GGI55Epc > > > > > > _______________________________________________ > > > 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 > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Matthew Herd Email: herd.m...@gmail.com Cell: 610-608-8930 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
