create bed leveling documentation. fixes #120

README.md

@@ -54,6 +54,7 @@ Due to the beta stage of Klipper Mod the documentation is not fully-completed. T
 - [Uninstall](docs/UNINSTALL.md): Uninstall Klipper Mod
 - [Slicing](docs/SLICING.md): Configure your Slicer for Klipper
 - [Wifi](docs/WIFI.md): Methods to Configure WiFi
+- [Bed Leveling](docs/BED_LEVELING.md): Leveling the bed, configuring Z offset, and bed mesh settings
 - [Linux Environment](docs/LINUX.md): Klipper Mod Linux environment
 - [Klipper Screen](docs/KLIPPER_SCREEN.md)
 - [Guppy Screen](docs/GUPPY_SCREEN.md)

docs/BED_LEVELING.md

@@ -0,0 +1,35 @@
+# Initial Calibration Before Printing
+Proper calibration is essential for achieving high-quality prints.
+
+If you’re experienced with other printers, you might assume that calibration involves adjusting the z-endstop using `Z_ENDSTOP_CALIBRATE`, calibrating the probe-to-nozzle offset with `PROBE_CALIBRATE`, and creating a bed mesh. Once done, you’d consider the printer ready to go. However, that’s not the recommended approach here.
+
+The Z-Endstop in this setup is deliberately positioned to prevent the nozzle from crashing into the bed, even if you switch to a thicker build plate and forget to create a mesh. For this reason, the Z-Endstop should not be adjusted. In fact, attempting to save changes to it will result in an error.
+
+In this system, the "z-offset" refers not just to the offset between the nozzle and the probe (as typically intended by Klipper) but also compensates for the lower z-endstop.
+
+Follow the steps below to ensure perfect first layers:
+
+## Step 1: Create a Heightmap
+1. Use the "Heightmap" option in the menu to create a heightmap, or the Bed Leveling option if you are using guppyscreen.
+2. Ensure the nozzle is clean and not leaking filament, as this can result in an inaccurate heightmap.
+3. Perform this step with the bed and nozzle at room temperature.
+
+**Important**: After creating the mesh, your printer still isn’t ready for printing. The nozzle-to-bed distance will be too large due to the Z-Endstop being intentionally offset.
+
+## Step 2: Adjust the Z-Offset
+While the default z-offset in the configuration works initially, it doesn’t account for the intentionally lower z-endstop. To address this, you’ll need to adjust the Z-offset using the well-known [paper test](https://www.klipper3d.org/Bed_Level.html?h=paper#the-paper-test).
+
+1. Move the toolhead to the center of the build plate (X=0, Y=0) with Z=2.
+2. Gradually lower the Z-axis to Z=0, ensuring the nozzle doesn’t come down too far and crash into the bed.
+3. Once at Z=0, continue lowering the nozzle in small increments by using "babysteps" to adjust the z-offset until the paper test indicates the correct distance. The nozzle should lightly grip a sheet of paper, allowing it to slide with slight resistance.
+
+Once the Z-offset is properly calibrated, save the new value with the `Z_ENDSTOP_CALIBRATE` command. Klipper will calculate the new Z-offset based on the adjustment.
+
+**Note**: This process invalidates the previously created heightmap. To avoid errors, delete the heightmap and save your configuration with `SAVE_CONFIG`.
+
+## Step 3: Recreate the Heightmap
+Now, recreate the heightmap by repeating Step 1. This time, the heightmap will account for the adjusted Z-offset and produce a more accurate representation of your bed surface. The new heightmap will reflect the corrected nozzle-to-bed relationship, ensuring optimal print quality.
+
+At Z=0, the nozzle will now be positioned precisely as determined during the paper test.
+
+With these steps, your printer is fully calibrated and ready to deliver high-quality first layers.