#linuxcnc-devel Logs

Feb 27 2019

#linuxcnc-devel Calendar

02:26 PM andypugh: I wonder if this code is redundant?
02:29 PM andypugh: https://github.com/LinuxCNC/linuxcnc/blob/master/src/emc/task/emctaskmain.cc#L1717
02:31 PM andypugh: I commented it out and homing still happens. I think that the joints get their home params from inijoint.cc instead:
02:31 PM andypugh: https://github.com/LinuxCNC/linuxcnc/blob/master/src/emc/ini/inijoint.cc#L194
02:31 PM andypugh: Both call emcJointSetHomingParams()
03:45 PM rene_dev_: andypugh a quick grep showed that the message type is not used
03:45 PM rene_dev_: tell me more about spindle homing
04:01 PM andypugh: I only plan on something very simple, run the spindle at a fixed speed until index reset.
04:04 PM andypugh: One use-case is spindle-orient, but you might need to re-home in some cases if, for example, the spindle encoder counter can’t handle top speed.
04:05 PM andypugh: (Which I suspect isn’t that unusual)
04:05 PM andypugh: It’s just a logical extension of the multi-spindle patch that makes spindles and joints converge a bit more.
04:09 PM cradek: my vmc's spindle encoder loses count if it gets much over tapping speed, and I don't care at all
04:10 PM cradek: if it used it for orient that'd be different!
04:16 PM andypugh: Yes, exactly. My old lathe was the same. It’s not a problem for threading and tapping.
04:17 PM andypugh: But if your VMC needed to orient the spindle for tool-change, then it would matter and you would want to re-home prior to orient as part of the tool change sequence.
04:19 PM cradek: definitely
04:20 PM cradek: mine orients with a pin and the vfd's jog input, which is the best way
04:20 PM cradek: the pin stays in, mechanically locking the spindle during the tool change
04:22 PM andypugh: And, also, it bugged me to have to re-type this FIXME: https://github.com/LinuxCNC/linuxcnc/blob/master/src/emc/motion/command.c#L1765
04:23 PM andypugh: I am not sure that spindle homing would ever be useful to anyone, really, but it just feels like it should be there. And I have tried to fudge it in HAL for someone at least once.
04:49 PM rene_dev_: cradek "much over tapping speed"
04:49 PM rene_dev_: I dont understand why you would tap at low speeds :D
04:50 PM rene_dev_: cradek yeah, samt pin shit on my haas
04:55 PM rene_dev_: if you dont trust the vfd to hold position during toolchange, why would you trust the other axis?