Using the math from that link below (202-200)/200=0.01 ==> inverted is 100:1.
Done the other way... If that's possible then (202-200)/202 = 0.0099009900... ==> inverted is 101:1 John > -----Original Message----- > From: Sam Sokolik [mailto:samco...@gmail.com] > Sent: March-22-21 6:19 AM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] Maybe a minimally printed harmonic drive? > > 202,200 for the outside spline and the flex gear is 200. In this situation > - the 202 tooth spline is stationary to the stepper. The 200 tooth outside > spline is mounted to the faceplate. In this layout - the ratio apears to > be 101:1 > > In this situation the stepper motor and the face plate spin the same > direction. > > With the same set of outside spines swapped - the ratio is 100:1 > > I am sure Andy can explain it. It doesn't make sense to me. > > Happy with runout... https://www.youtube.com/watch?v=eLyP2YwdstQ > > sam > > On Mon, Mar 22, 2021 at 12:58 AM John Dammeyer <jo...@autoartisans.com> > wrote: > > > > > > > > From: Sam Sokolik [mailto:samco...@gmail.com] > > > So..... interesting.. I just swapped the gears.. Before my ratio was > > > 100:1. Input scale was 1600step/rev * 100 = 160000/360 = 444.4444444 > > > input scale. > > > > > > Now I reversed the outside splines. I thought - wow - I must be losing > > > steps - but i would aways come back to zero. Finally though - maybe the > > > ratio was now 102:1 - no. over shot. > > > > > > so the final solution seems to be 101:1 WTH? > > > > > > sam > > > > Hi Sam, > > I found this at: > > https://www.engineeringclicks.com/harmonic-drive/ > > > > "The rate of rotation is dependent on the rotation of the input shaft and > > the difference in the number of teeth between the flex spline and the > > circular spline. The flex spline has fewer teeth than the circular spline, > > so it can rotate at a much reduced ratio and in the opposite direction than > > that of the input shaft. The reduction ration is given by: (number of flex > > spline teeth � number of circular spline teeth) / number of flex spline > > teeth. So for example, if the flex spline has 100 teeth and the circular > > spline has 105, the reduction ratio is (100 � 105) / 100 = -0.05 which > > means that the flex spline ration is -5/100 (minus indicates the opposite > > direction of spin). The difference in the number of teeth can be changed to > > accommodate different reduction ratios and thus different specialized needs > > and requirements." > > > > So how many teeth have you on the fixed verses flex gear? And did you by > > chance miscount? > > John Dammeyer > > > > > > > > > > > > _______________________________________________ > > 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