I installed my BLTouch about a month ago by following jturrell's directions
, and I love it so far.
My notes to add:
- The black & white wires from the BLTouch that replace the Z end stop don't just behave as an open/closed switch, polarity matters. If your M2 has trouble homing the Z-axis, meaning It keeps raising the bed after contacting the BLTouch causing the BLTouch sensor alarm to activate (indicated by it's LED flashing) and then lowers the bed a couple centimeters try swapping where the black & white wires are connected. For me the white wire had to be connected to the center pin of the Z-Min header and the black wire to the pin furthest away from the X/Y min headers.
- My "#define Z_PROBE_OFFSET_FROM_EXTRUDER" value ended up needing to be -1.10 instead of jturrell's -2.05. Do not forget to calibrate this value because it will vary for your printer, and way you mount your BLTouch.
- I also decreased the settings "#define Z_RAISE_BEFORE_PROBING" from 30 down to 10, and "#define Z_RAISE_BETWEEN_PROBINGS" from 15 to 5 to speed the probing process up just a little. They could probably be lowered even more, but those are good even values.
@ryaneb85, I leveled my bed right before I installed the BLTouch, and noticed that the center of my bed is higher than the outer edges no matter how I adjusted the leveling screws, it's not much but I can feel the difference in resistance when I slide a folded over piece of paper between the nozzle and the bed. When I print I can see the plastic knob on the Z-axis rotate very slightly as the printer adjusts for this while it prints.