On Sat, 2013-11-02 at 09:19 +0000, Steve Blackmore wrote: > On Fri, 01 Nov 2013 08:22:26 -0700, you wrote: > > >Hi all, > > > >I've often wondered how well a rotary table would work if driven by a > >reasonably stiff timing belt. Say 1" urethane with steel fibers. > >Gearing would be approx 5:1 and then a reducer if necessary to couple to > >the servo motor. Encoder would be mounted on an idler wheel driven by > >the 1" belt. I use a similar encoder setup on the Z axis of my mill and > >it seems to give rather good control at ~ 100K counts/inch. ;-) > > > >Has anyone tried this or something similar and what were the results. > >Stiff enough? Accurate enough? Of course everyone's definition of > >adequate is different but was it good enough to be usable? > > Timing belts will work accuracy wise on positioning, but stopping > cutting forces being directly passed back to the drive is a problem. > > That's why worm and pinion type gearing is used, and you have to be > careful with that. I did some development work using worm and pinion > gearboxes and under 30:1 it was possible to back drive the input shaft. > Over that they were self locking. > > Steve Blackmore > -- Thanks Steve. That was the information I was looking for. My application has pretty light loads so it might still work but there are no guarantees.
Andy .. so why use a fancy resolver unless you really need the ruggedness? It is so easy to just attach a high res encoder to linuxcnc. :-) I appreciate all the feedback and discussion. Dave > > ------------------------------------------------------------------------------ > Android is increasing in popularity, but the open development platform that > developers love is also attractive to malware creators. Download this white > paper to learn more about secure code signing practices that can help keep > Android apps secure. > http://pubads.g.doubleclick.net/gampad/clk?id=65839951&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Android is increasing in popularity, but the open development platform that developers love is also attractive to malware creators. Download this white paper to learn more about secure code signing practices that can help keep Android apps secure. http://pubads.g.doubleclick.net/gampad/clk?id=65839951&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
