Turning - Use Reduced Speed and Feed - parting operation

[jason23]

I'm using inventorcam and the option for use reduced speed and feed i see it has a variable (125rpm that you can't change) for the reduced speed.  The post i am currently using for a DMG Mori NLX2500SY only outputs the reduced feed and i'd like it to change the speed as well in the code it posts out.  I'm currently editing my code by hand to drop the speed down so the part drops off nicely into the parts catcher.

[CNC_Lee]

@jason23 

If the generic posts are not providing the required output, I offer post processor development services and happy to work out a solution for your machine! Please message me if still needing assistance.

[bob.schultz]

Hello @jason23,

Perchance do you have the Use Constant Surface Speed box checked in the Tool tab?  Inventor does not allow you to use a reduced spindle speed when using SFM spindle speeds.

[jason23]

Ok, that was it, although it doesn't really solve what i'm trying to do unfortunately.  

I'd like to use constant surface speed up until the last .25" when parting off, then drop the RPM down to 125-250rpms to part off the last little bit and have it drop nicely into the parts catcher instead of flying all over the machine.  I currently hand edit it alot to get it do what i need to do, but would love a simpler solution.

[bob.schultz]

Try adding the following function to the post and see if the output works for you.  It uses a hardcoded value of 125 RPM for the spindle speed, but this could be made into a property if need be.

function onMovement(movement) {
  switch (movement) {
  case MOVEMENT_REDUCED:
    if (getParameter("operation-strategy") == "turningPart" && tool.getSpindleMode() == SPINDLE_CONSTANT_SURFACE_SPEED) {
      writeBlock(
        gSpindleModeModal.format(getCode("CONSTANT_SURFACE_SPEED_OFF", PART)),
        sOutput.format(125),
        mFormat.format(getCode(tool.clockwise ? "START_SPINDLE_CW" : "START_SPINDLE_CCW", getSpindle(PART)))
      );
    }
    break;
  }
}