Ender 3 Pro BL Touch nightmare

Please help…

I’ve tried to download Visual Studio to compile my own firmware, but I keep getting errors in the PlatformIO installer and I’ve tried this on two different machines. Which lead me to a CHEP video and he recommended this site that does daily firmware builds. I tried the firmware on the Creality website for the BL Touch and when I enter in the Z offset, and do auto home, the hot end crashes into the bed and I have to quickly power off the unit.

I have a newer Ender 3 Pro with the 4.2.2 board and I just installed this firmware:
https://marlin.crc.id.au/firmware/Ender%203%20-%20v4.2.2%20Board%20-%20BLTouch/

The firmware loads up and I can auto home, but I can’t figure out how to set the Z axis off set. It keeps going to Z axis 10. If I try to adjust the Z axis, it won’t go below 0.000.

Can someone please assist?

Thank you!

Here is a video of what is happening:

The Z axis is not supposed to go below zero. This tells the printer you want to move your nozzle below the bed.

Once your printer is homed, use the Z-Offset wizard to calculate your Z-Offset.

Going below 0 on the Z axis is a recipe for trouble.

Thank you for the information, can you please explain more about the homing process?

Here’s rundown on the Marlin G28 homing function:

Does that need to be compiled or something? How do I do that from the screen?

I read more into the g codes and you need to have the printer connected to a computer… Can you please make a firmware that allows negative Z axis movement for people? I see other people asking for this as well in the forums here and I understand there is chance of damaging my equipment. Please and thank you.

I don’t mean to sound rude, but the fact that you don’t understand what homing is, but want to enable an option that can easily damage your printer and throw everything out of alignment is exactly why this option is not turned on by default.

It would be irresponsible for me to do so.

I had exact same problem.

this thread on reddit helped.

This Link/Solution

After homing the printer, the head should be in the middle of the bed and 10mm for the Z axis. this is the default position.

  1. Home the printer
  2. Select Configuration then Probe Z Offset
  3. It should be set at -00.000
  4. turn the dial to increase the minus offset. (Mine is -00.900) Try setting it to -00.600
  5. Press the button to exit then scroll down to Save Settings (should receive a beep)
  6. Home the printer again, Your Z setting should read 10.6
  7. Move the Z Axis to 00 and check the head gap.
  8. Do procedure 2 to 7 increasing the offset each time until the head is the correct distance.
    There is probably quicker and easier ways but I found this procedure worked for me