On 26 March 2013 00:59, jeremy youngs <jcyoung...@gmail.com> wrote: > i like the idea of using a capstan with offsetting weight , if you > use 2 motors for x,y then use the same weight in tension the motors > will see nothing but frictional resistance . If your capstan is > sufficently large you should see very good accel and top feed rates ,
I am not sure you will see good acceleration. In fact, it is always going to be less than 1g. This is because for any faster acceleration the strings go slack as the weighs don't fall fast enough. I think bicycle chain might be the thing to use for the "string". I think that a grooved drum, sat on a spline and free to slide vertically could be guided by a wheel engaged in the groove. As an alternative to the spline, it could be driven by a toothed-belt pulley several times wider than the belt. Or (thinking out loud) a square drive-shaft in the middle of the drum and some ball-bearings to drive it. (4 of the ever-popular V-groove style) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ Own the Future-Intel® Level Up Game Demo Contest 2013 Rise to greatness in Intel's independent game demo contest. Compete for recognition, cash, and the chance to get your game on Steam. $5K grand prize plus 10 genre and skill prizes. Submit your demo by 6/6/13. http://p.sf.net/sfu/intel_levelupd2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
