I've built a single axis CNC based on the C-Beam and using an Arduino UNO running GRBL 1.1f. If I move the CNC to < 10 mm from the limit switch and perform a $HX it homes perfectly. If I am any further away it moves a bout 5mm and pretends to home but wherever it is. It will not move far enough to find the limit switch. The switch common is on Ground and the NO is on pin 9 of the UNO. I have a 10K (tried 500R) resistor from pin 9 to +5v. I also have a 104 cap between the pins. It all works well IF I am already close to the switch. I have played with $130 using huge values and small. I must get this going for a job. Any help would be much appreciated. $0=10 $1=25 $2=0 $3=0 $4=0 $5=0 $6=0 $10=19 $11=0.010 $12=0.002 $13=0 $20=0 $21=0 $22=1 $23=1 $24=50.000 $25=500.000 $26=250 $27=2.000 $30=1000 $31=0 $32=0 $100=200.000 $101=250.000 $102=250.000 $110=3000.000 $111=500.000 $112=500.000 $120=10.000 $121=10.000 $122=10.000 $130=800.000 $131=200.000 $132=200.000 From config.h #define HOMING_CYCLE_0 (1<<X_AXIS) #define N_HOMING_LOCATE_CYCLE 1 #define HOMING_SINGLE_AXIS_COMMANDS #define HOMING_AXIS_SEARCH_SCALAR 20 //I know this was 1.5 but I've tried 1.5, 6, 10 ,20 #define HOMING_AXIS_LOCATE_SCALAR 10.0
I've not calibrated my steps yet. But I did change out the capacitor (same value) and it is now working. I don't know how, but I'm not asking questions at this point, just thankful it's working properly regardless of the travel. It now homes perfectly. Thanks.
ah, you must have it actually moving the correct distances before you can expect homing to work correctly. HOWTO Calibrate your CNC Machine for MACH3 or GRBL or the wizard in openbuildsCONTROL