XYZ Probe Offset Calibration Tool for BL CR 3D Touch

This is a tool to help you find the correct z-offset, x-offset, and y-offset for your BL Touch, CR Touch, or 3D Touch bed leveling probe.

Print all 3 parts and then super-glue the corner clips on the two tips as pictured. You will need a rubber band that can stretch over the opposite corner of your bed.

Update: Added Version2 for those who prefer X-marks-the-spot. Same instructions as below, it just uses X's instead of circles. (Might be a little easier to see when the nozzle touches the tool for z-calibration)

How to use this tool:

Step 1
Auto Home your printer without the tool in place.

Step 2
Raise the Z-Axis using the display about 100mm (Do not disable steppers).

Step 3

After you auto home your printer and raise the Z-Axis as stated above, place the tool in the front left corner of your print bed and then hold in place using a rubber band stretched over the peg and the opposite corner or your print bed. Make sure it is square, the tool and rubber bands should ensure that.

Step 4

Deploy your probe.

Step 5

Using your printer control (again, do not disable stepper motors), adjust the X and Y to position the probe directly over the center of the circle labeled PROBE. Slowly lower the Z-Axis until the probe barely touches the tool surface in the center of the PROBE circle. Your probe should then light up (and retract).

Step 6

Write down the current position of X, Y, and Z on your display . Label these positions X1, Y1, and Z1.

Step 7

Next, using the control again, position the nozzle directly centered over the circle labeled NOZZLE. Slowly lower the Z-Axis until the nozzle touches the center of the NOZZLE circle.

Step 8

Write down the current X, Y, and Z position on your printer display and label them X2, Y2, and Z2.

Step 9

Because the holes should be exactly 50mm apart, add 50 to the number you wrote down for X1. You can use digital calipers to . Some filaments expand or contract more than others.

BTW, If you need digital calipers or rubber bands I have provided a few links here:
Digital Calipers: https://amzn.to/48G64VR
Rubber Bands: https://amzn.to/46AjFMu

Step 10

If your probe is mounted to the left of your nozzle (usually the case)...

Subtract the X2 value from the X1 value and that is your X-offset.
Subtract the Y2 value from the Y1 value and that is your Y-offset.
Subtract the Z2 value from the Z1 value and that is your Z-offset.

Step 11 (Last one, I promise!)

Store these values in your printer, save, and remove the tool from your printer bed.

You can use your slicer software or Octoprint to set X, Y, and Z offsets if you cannot set them using your printer control . You can use G-Code before a print job starts to do this. For example:

M851 X-43; sets the x-offset to -43
M851 Y-6; sets the y-offset to -6
M851 Z-1.25; sets the z-offset to -1.25
M500; stores the settings. This M code may not work with all printers.

When you auto-level your bed, the leveling probe points should all be equal distances from the edges. The center position should be exactly in the center.

Notes:

It is possible on some printers that X-Axis cannot go all the way to the edge of the bed surface. This is why your bed surface is usually 235mm x 235mm (on and Ender3 for example), but your build space is 220mm x 220mm. This is because the end stop for the X-Axis prevents the hotend from going all the way to the left. If you look at it closely when you auto-home, you will see that the nozzle cannot go all the way to the edge without hitting the X end stop switch. This is normal and part of the printer design.