On 17 September 2014 13:59, <p...@wpnet.us> wrote: > 1. The biggest issue currently - After some fiddling I have the Hitachi VFD > controlled spindle operating in the PnCConf open loop test where I am able to > run it forward and reverse at various speeds. I have the spindle encoder > connected (A and Index only, not sure on CPR currently) and in HALscope I can > see the A pulses and index pulse. I haven't been able to get the spindle to > operate in LinuxCNC however no matter what I've tried. Another issue I have > found is that when running in reverse and stopping, LinuxCNC drops the > direction line before the VFD has completed the decel ramp, causing the VFD > to slam the lathe into forward for the duration of the decel, obviously not a > desirable thing.
I can see why that would happen, but that isn't what I see with my lathe/vfd so I suspect that it is something to do with the config at the VFD end. I think it is best to configure the VFD for "two button" operation with one terminal for FWD and one for REV. Then when the spindle-fwd or spindle-rev signals go false then the VFD simply switches off and ramps down at its internally programmed speed. It sounds to me like you may have the VFD wired for ON/DIR rather then FWD/REV. I am having trouble reconciling the statement that you can't get the spindle to work with LinuxCNC with the statement that something funny happens when LinuxCNC drops the dir line. > 2. I've got the axis homing working in the direction it seems to want to run, > i.e. in the negative direction, however this seems like a bad idea on a lathe > to me. If I have a part in the spindle and need to re-home for some reason, > something not unexpected on a stepper machine, homing in the negative > direction will crash the toolpost into my part. It would seem better to home > in the positive direction and "zero" to the max travel of the axis. I haven't > figured out how to do this. This is a matter of setting the signs of the search and latch velocities in the INI. My lathe homes in the positive X and negative Z direction (as homing into the tailstock sounded like a bad plan). > 3. The lathe has an 8 position unidirectional stepper driven tool turret with > a home switch. I currently have the stepper drive wired to stepgen 2 (0=Z, > 1=X). I was able to configure an A axis so I can manually move the torret, > but I've not found any docs so far that give me much of a starting point to > figure out how to configure the tool turret properly for automatic changes. There are HAL components to control that style of changer here: http://wiki.linuxcnc.org/cgi-bin/wiki.pl?ContributedComponents#Boxford_Lathe_ATC_toolchanger_component They may need tweaking for your particular application, but help will be available with that. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ Want excitement? Manually upgrade your production database. When you want reliability, choose Perforce Perforce version control. Predictably reliable. http://pubads.g.doubleclick.net/gampad/clk?id=157508191&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
