You have a choice of either Z axis Step output or Spindle output for your pen operation, Fix the decision in your mind and don't get side tracked, i did whilst typing this reply. Keep it simple, you can then alter Spindle speed etc to see what effect it has on the servo. Keep the default settings - grbl will quite happily run without any hardware connected, as soon as you change the settings you end up needing limit switches connected and to home imaginary axis. If you happen to have a uno lying around or you can breadbord the nano so that you can connect the servo without the CNC board, Upload GRBL 1.1 to it and see what happens when you send an NC file Or just simply send Spindle commands, Min/max can be any value just remember pen up will = max and down=min (or inverted you decide). I don't know what effect pwm has on the servo the two signals are different but many have had success without changing anything. Just make sure you are not falling down their hole. It sounds like the guys in link bdring/Grbl_Pen_Servo#1 (comment) are using version 0.9 of GRBL as they are talking about the Z End stop. It sounds like the board programmed to run just a servo code works using -Z pin (pin 11 which also corresponds to GRBL Spindle ver 1.1). Have you tried any of the suggestions made in that thread. There will be examples on the web where people have built plotters and changed the code to operate a servo or a solenoid. Actually you are building a 3 axis machine but the Z isn't required to have variable height? I'm confused by the requirement of a spindle when you are using a plotter pencil.Ĭonverting the z axis from step to servo control for up/down of the pencil is more the issue you have. The spindle output by default is pwm for variable spindle, i believe there is some trickery involved with setting up for lasers but out of the box it should do exactly what you want M3 and M5 will control a spindle with speed set by S*** speed (gcode - M3 S1000 will start a spindle running at 1000 Rpm all be it that the output signal will be 0-255 pulse width.)
0 Comments
Leave a Reply. |