Hi All, I am a CNC machinist by profession and own a CNC machine shop. I build 3D printers as well. Anyway got the idea to build a laser and constructed a metal frame powered with Nema 17, arduino Uno clone by static boards and a V3 CNC shield. I have 2 limit switches wired in series to act as Normally Closed in X and Y axis and a Z axis limit switch . I have Z limit switch NC in Z+ Here is my grbl settings below... My problem is that Z will not home. At first it would not even move then I undefined in Config.H the VARIABLE_SPINDLE then Z started to move. At first I had the machine fitted with A4988 Stepper drivers. My machine used to make the homing action in Z as if it has reached the microswitch. Just lift up and down a few mm, then proceed to home X and Y. This action does not even touch the Z homing switch but X nad Y homes seamlessly. I then fitted the DRV8825 with the three jumpers fitted. I made the settings relevant to the stepper in terms of steps per mm etc etc. When disabling the homing everything works just fine. When enabling homing, when I home, the Z would creep up slowly making a strange noise and if I touch the Z limit switch nothing happens. Through the verbose output< i know the switches are working. I also tried hooking a small switch on the CNC shield to test if the issue was interference but it behaves exactly the same.... I am stuck guys so any assistance appreciated as I have been in this hole for a week. when disabled, i can jog and the limit switches work seamlessly. I have come across someone who suggested using the D12 pins but I have tried to check via the verbose output but there is no response. I am looking for some help. Thanks in advance... Tonio ... **** Connected to COM11 @ 115200 baud **** Grbl 1.1h ['$' for help] >>> $$ $0 = 10 (Step pulse time, microseconds) $1 = 25 (Step idle delay, milliseconds) $2 = 0 (Step pulse invert, mask) $3 = 0 (Step direction invert, mask) $4 = 0 (Invert step enable pin, boolean) $5 = 1 (Invert limit pins, boolean) $6 = 0 (Invert probe pin, boolean) $10 = 1 (Status report options, mask) $11 = 0.010 (Junction deviation, millimeters) $12 = 0.002 (Arc tolerance, millimeters) $13 = 0 (Report in inches, boolean) $20 = 0 (Soft limits enable, boolean) $21 = 1 (Hard limits enable, boolean) $22 = 1 (Homing cycle enable, boolean) $23 = 7 (Homing direction invert, mask) $24 = 250.000 (Homing locate feed rate, mm/min) $25 = 10.000 (Homing search seek rate, mm/min) $26 = 250 (Homing switch debounce delay, milliseconds) $27 = 1.000 (Homing switch pull-off distance, millimeters) $30 = 1000 (Maximum spindle speed, RPM) $31 = 0 (Minimum spindle speed, RPM) $32 = 0 (Laser-mode enable, boolean) $100 = 161.250 (X-axis travel resolution, step/mm) $101 = 161.250 (Y-axis travel resolution, step/mm) $102 = 833.000 (Z-axis travel resolution, step/mm) $110 = 3000.000 (X-axis maximum rate, mm/min) $111 = 3000.000 (Y-axis maximum rate, mm/min) $112 = 1000.000 (Z-axis maximum rate, mm/min) $120 = 100.000 (X-axis acceleration, mm/sec^2) $121 = 100.000 (Y-axis acceleration, mm/sec^2) $122 = 100.000 (Z-axis acceleration, mm/sec^2) $130 = 630.000 (X-axis maximum travel, millimeters) $131 = 200.000 (Y-axis maximum travel, millimeters) $132 = 150.000 (Z-axis maximum travel, millimeters) ok >>> $G [GC:G0 G54 G17 G21 G90 G94 M5 M9 T0 F0]
Your issue may be the V3 cnc shield does not have the right pinouts to run stock GRBL 1.1 -- particularly for the z axis. It has to be a V3.1 or higher board. See the pinouts here gnea/grbl. Unless you actually remapped it. If so than ignore me. D12 is the z limit switch in Grbl 0.9 or higher.
