On 11/03/2011 10:31 AM, andy pugh wrote: > On 3 November 2011 16:14, Jon Elson<el...@pico-systems.com> wrote: > > >> This allws the machine to home with a varying amount of racking of the >> gantry >> each time it is homed. This seems like a really poor choice. >> > Now you mention it...Yes. > > I was imagining that switches (or the dead-stop that Tom has been > experimenting with) would do the squaring. Though then I don't know > why you would bother with the index. > If you want totally repeatable positioning, and want to assure the gantry beam is absolutely square to the gantry rails, then you need precise repeatability of the home position. If the beam is not square, then the axes are not orthogonal. Home switches are good, but the home to index gets you down to the exact encoder count, so you know the racking of the gantry is identical each time.
Jon ------------------------------------------------------------------------------ RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
