Hi Dave, I'm sure someone will correct me if I'm wrong; so here goes.
The way index homing works is that after the homing switch actuation is detected, the next index pulse sets the home position. If, by bad luck, the edge of the index pulse is right at the switch edge, a little jitter might cause it to be missed. Then the next index pulse will be considered home. Let me guess. The distance between index pulses on your machine is .531-.505 = .026. So I would say the distance is 25 thousandths. The solution to your problem is to move your home switch by around 12 thousandths. Ken Dave Engvall wrote: > Hi all, > > Finally found a 'roundtoit'. > > As a quick test of homing repeatability I mounted a piece of 6061- > T6 in the vise, wrote a small program to > move from homing position to the workpiece and then drill a 1/2" hole > using a 0.500 carbide endmill. > > Hole 1 was drilled repeatably after a shut down and restart of emc > including homing. > As a check I drilled hole 2 only one time. > > Hole 1 x = 0.531 y = 0.506 > Hole 2 x = 0.505 y = 0.506 > > Using a dial indicator I checked the repeatability of Z home. It was > within a thou using a Enco 1" indicator. > If this gets serious I will use a better indicator however I don't > see a problem with Z. > > So ... back to the X axis. > > Fire up halscope.. monitor axis.0.home-state, axis.0.index-enable and > Xindex. > > These may not be the correct variables to monitor but they looked > like a good start to me. > > when axis.0.home-state goes to 16 both axis0.index-enable and Xindex > go to 1. > > axis.0.home-state has a series of increasing values > > 0 > 4 then shortly 5 > 11 the shortly 12 > and finally 16. > > What else do I need to look at? > > I did not do the obvious and try the same variables with halscope on > either Y or Z. Duh! > Only thought about it after I had shutdown everything. > > Hope this is enough information to diagnose the problem or recommend > more troubleshooting. > > Thanks in advance for any help. > > Dave > > > ------------------------------------------------------------------------- > This SF.Net email is sponsored by the Moblin Your Move Developer's challenge > Build the coolest Linux based applications with Moblin SDK & win great prizes > Grand prize is a trip for two to an Open Source event anywhere in the world > http://moblin-contest.org/redirect.php?banner_id=100&url=/ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users -- Kenneth Lerman Mark Kenny Products Company, LLC 55 Main Street Newtown, CT 06470 888-ISO-SEVO 203-426-7166 ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
