Mount for the BL Touch for the Ender 3 and similar probes and machines

This wing is designed to hold a BL Touch in position for the Ender 3 (Ender 3 Pro), and all other printers with similar X-carriage (many Tevo's, CR-10, etc.).

It is specially designed to allow access to the hotend without having to dissamble the BL Touch every time. You can reach the 2 screws without any problems.

Assembly

1. Print all the parts
2. Fixate the BL Touch to the holder with two M3 bolts and two nuts
3. Fasten the holder together with the stock metal box, with two M3x10 bolts. Don't finish fastening all the way
4. Place the shim between the metal plate and the holder. Finish screwing the bolts. (The shim is a separate part from the holder to make it easier to print).
5. It depends on your hotend and nozzle configuration. If, when homing, the nozzle touches the bed before the deployed BL Touch does, then you need to place a spacer between the BL Touch and the holder. Just make sure it doesn't touch the print when un-deployed.

Extra Hardware

• 2 x M3 bolts at 10mm length (the original ones are 8mm length)

Optional:

• 2 x M3 spacers

Probe Offsets

• X axis: 51.1 mm to the left
• Y axis: 8.3 mm to the front

Marlin 1.x configuration:

#define X_PROBE_OFFSET_FROM_EXTRUDER -51.1
#define Y_PROBE_OFFSET_FROM_EXTRUDER  -8.3
#define Z_PROBE_OFFSET_FROM_EXTRUDER   0

Marlin 2.x configuration:

#define NOZZLE_TO_PROBE_OFFSET { -51.1, -8.3, 0 }

Z-Offset

Z-Offset depends on your particular machine and hotend and can even change with diffrent nozzles and bed/nozzle temperature! You'll need to calibrate your own Z-offset.

Your Z-Offset should be negative, meaning the probe (when the prong is extended) is touching the bed before the nozzle does.

If your Z-Offset is zero or positive, it just won't work, because the nozzle will push the bed down, and the "measurement" will be meaningless. For that, print the "BL Touch 2mm spacer.stl" and use it as a spacer as needed. You can scale the spacer in the Z dimension (non-uniform scaling) to suit your needs.

A typical Z-offset is about -2.0mm. The probe should be low enough so it will hit the bed before the nozzle when extended, and high enough so it won't enter in contact with the printed part when contracted.

Compatibility

Tested Machines:

• Ender 3

Tested Probes:

• 3D Touch by Triangle Labs (AliExpress)

Updates

July 21 2020 -- updated the designs of the holder and the spacer to allow access to the center screw of the BL Touch.