CNC Strangeness

cnc pause

Strange issue with CNC machine. It runs, does a plunge, then it just stops. The controller makes a noise when it stops. I wonder if it’s crashing because of some funny g-code?

4 thoughts on “CNC Strangeness

  1. If the g-code were the problem, then the PC would be the source of the error and mach3/emc2 would be to blame, nothing to do with the driver…

    Since mach3/emc2 convert the g-code to timed pulses and route them thru the parallel port, the stepper driver is “dumb” to anything but pulses, it has no idea about g-code.
    In other words, the stepper drive has no intelligence, all it does is respond with a step when it senses a pulse on the particular parallel port pin…

    So… if the driver is indicating a problem or making strange sounds, it’s likely one of two things, an over current protection going active or a wire is loose.
    It’s very likely your driver will sense for wire disconnect, most of the ebay drivers are based on the TB6560 chip which has this feature.

    The only alternative being…
    Unless your driver has a g-code interpreter, in which case it wouldn’t use the parallel port and it wouldn’t need mach3/emc2…
    It would be either usb or sd-mem, like the cupcake, where the g-code gets parsed on the on board MCU and converted to pulses…

  2. It looks like it triggered an error of sorts, the way the driver lights indicate…
    Possibly, a loose connector to a motor or an over current limit was triggered by something binding or a dirty linear bearing?

    The only possible G-code that would cause this would be something outputting too many steps/sec…
    In other words, G-code shouldn’t cause this, the PC is just outputting a series of pulses (steps) and the driver has no clue what the gcode is…

    Michael

    • Hi Michael,

      Actually, I ran the same g-code through my g-code tester and it gave a pile of errors. I didn’t note what they were but it made sense that if the g-code threw errors in the validation system and it also crashed the controller, it points to the g-code a bit stronger.

      I regenerated the g-code with a different tool path and it worked fine.

      The g-code was made from Sketchup using the phlatboyz plugin.

Comments are closed.