On Wednesday 22 April 2015 08:10:57 Les Newell wrote: > Hi Gene, > > I believe the lower belt is glued to the track so it cannot move, > effectively making it a rack. > > Les
Effectively 2 belts facing each other with symmetrical mirrored tooth profiles? Likely as good a rack as you could buy, at 10% of the cost per foot compared to a machined rack. I am still impressed. In such a situation I see a bidir spec of .002" tolerance, would this be a cyclic error that could be calibrated out by mapping it? Seems like it should be to me. With an index pulse from a stepper driver to home the error map to, even steppers could be used at the finer division ratios. My 1/8 I use with the screws which are much slower would be too coarse a move. My 2m542 drivers can go to /25. Since I have a 5i25 on the lathe, and the speed limit for the opticals in the 2m542 is a touch better than 300 kilohertz, I ought to do some experimenting with an eye to reducing the 2/1 reduction gear noise. Need a round tuit I guess. :( I am dreaming of course, no stepper driver I know about puts out an index at its power up default position, or when going by it, or even a once per rev pulse, nor are our stepper drivers capable of using it. Out of I/O pins is probably the biggest roadblock as that would take 2 more pins per axis. But I don't know of a law that says we can't dream, :) Glad to hear from you, I was afraid you had dropped off the list. > > On 22/04/2015 13:02, Gene Heskett wrote: > > Certifiable slicker than snot on a doorknob. I can see why they > > would patent it. I wonder how long till it would take to stretch > > enough to not lay dead flat on the track? 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> ------------------------------------------------------------------------------ BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT Develop your own process in accordance with the BPMN 2 standard Learn Process modeling best practices with Bonita BPM through live exercises http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_ source=Sourceforge_BPM_Camp_5_6_15&utm_medium=email&utm_campaign=VA_SF _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
