On 06/13/2013 01:52 AM, andy pugh wrote: > On 13 June 2013 03:25, Kirk Wallace <kwall...@wallacecompany.com> wrote: > >> One is supposed to engage the half-nut when the indicator reaches an >> appropriate location. I suspect the ELSs have an index sensor so they >> know when to start the thread, just like LinuxCNC. > > If they stop the carriage, let you wind out the cut, then reverse to a > fixed point, then that can work. > If they release the nut and leave you to wind the carriage back, then > it can't engage the nut unless you wind back to exactly the same spot > every time (or the nut will drop into the wrong tooth-gap, or no > tooth-gap at all) >
Depending on the thread pitch, there are one or two threads per leadscrew revolution. One's choice of change gears sets this up. The indicator lets you know where in the revolution the screw is. As long as the leadscrew, spindle and indicator remain engaged, if one engages the half-nut _anywhere_ on a full, or a half-rev mark on some threads, the tool will be on the thread groove, . No stopping or rewinding needed. The ELS takes the place of the spindle to leadscrew and indicator gearing. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/ ------------------------------------------------------------------------------ This SF.net email is sponsored by Windows: Build for Windows Store. http://p.sf.net/sfu/windows-dev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
