---------------------------------------- > Date: Wed, 29 Oct 2008 19:25:33 -0400 > From: [EMAIL PROTECTED] > To: emc-developers@lists.sourceforge.net > Subject: Re: [Emc-developers] spindle brake > > [snip] > >>Thanks Chris. >>Maybe we could get John or Alex to mention this behavior in the docs please. >>I would think that a pause for up to speed would be very important for >>constant surface feed. >> >> > You can do this with HAL. You can compare the spindle speed to the > expected speed, and activate feed hold until it gets within range. (I'm > assuming that CSS/FPR/threading honor feedhold, which is another can of > worms) You'd probably want to set some digital output in the G-code to > allow this behavior - you may not want motion to stop every time there's > a speed change. > > - Steve >
Yes you are right but that is a hack, IMHO -CSS should always wait for an up to speed signal before STARTING feed otherwise the surface feed might not be even close. The threading should only feed hold when it's not synced in my opinion. Thats they way the Okuma was- If you hit feed hold (in the middle of a pass) it would hold after the current thread pass was finished. or it should other wise ignore feed hold totally till threading command done. As for the spindle brake/reverse problem sort of the same thing- EMC should not go from m3 to m4 (or vice versa with out stopping first and it should know if it did stop. Simple machines could just connect spindle-has-stopped to spindle-brake. I can do this also by monitoring the three spindle pins fwd, rev, brake and using feed hold while changing. What we need to do this safely is a feed hold that cannot be by-passed . the current feed hold can be overridden. the spindle_brake pin should actually be called spindle_stop (what one does with the signal is up to the integrator) as that is more accurate but now I'm nit-picking :) _________________________________________________________________ ------------------------------------------------------------------------- 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-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
