Hi! I recently swapped out an arduino/Gshield for a Spark Concepts xPro. After this switch, I have to put in a very high value (1282) for steps per mm on the Z axis for to move the correct distance while calibrating. Is this indicative of a possibly bigger problem? The steps per mm for the X and Y axis are only 40 steps per mm. What could be causing this? Thanks! Here are the rest of my grbl settings: $0=10 $1=255 $2=0 $3=6 $4=1 $5=0 $6=0 $10=1 $11=0.020 $12=0.002 $13=0 $20=0 $21=0 $22=0 $23=1 $24=25.000 $25=500.000 $26=250 $27=1.000 $30=255 $31=0 $32=1 $100=40.000 $101=40.000 $102=1282.000 $110=5000.000 $111=5000.000 $112=500.000 $120=250.000 $121=250.000 $122=50.000 $130=790.000 $131=790.000 $132=200.000
check the microstepping setting on the Z driver. what is the leadscrew pitch? you only need enough microstepps to give you 0.01mm per step.
With an M8 with 1.25 pitch at 1/8 microstepping, 1280 is the steps/mm according to this RepRap Calculator - Prusa Printers But, I do not know if that is the screw you are using. It was just a guess since the math works. Are you using belts with a 20 tooth pulley at 1/8 microstepping on X and y?
Set your value to 400 steps per mm (using x16 microstepping/interpolation) for the T8 lead screws from openbuilds.
You need to change the microstepping setting on the Z axis driver, it appears to be x8 which is giving this high value which is also EXCEEDING the GRBL max step rate Z (micro)steps per mm: 1280.000000 0.00078125mm per step Z max steps/s: 42666.666667 Greater than 30kHz! reduce to x4 and you can run happily at Z (micro)steps per mm: 640.000000 0.0015625mm per step Z max steps/s: 21333.333333 but this may limit your max speed on Z, reducing the microstepping further to x2 Z (micro)steps per mm: 320.000000 0.003125mm per step Z max steps/s: 10666.666667 will allow a higher max speed while retaining pretty good resolution. in other words, on the board you see this and you need to move the uSTEP jumper jumper settings at Spark-Concepts/xPRO turn everything off before changing the jumpers