Cut off top ends of safety pin. Insert the left leg into the small hole at the top of the printed Z-probe holder and bend the pin so that the loop aligns with the hole. Secure with one of the M2.5x12 screws.

Fit the micro-switch with the cable leading to the right, using another two M2.5x12 screws.

Then insert the hex key into its groove/hole from above.

While hex key is in upper position, fit the spring and terminal block from below, compress the spring about 80% (not 100% as shown in the picture!), and tighten the terminal screws.

Trigger the probe by flicking the short leg past the safety-pin spring into the deployed position.

Push from below against the probe leg until the hex key pushes back up past the safety-pin spring. Check that it retracts correctly.

Push from below against the probe leg until the hex key pushes back up past the safety-pin spring.

Repeat several times to confirm that the probe will work reliably. You may need to oil or grease the brass rod during commissioning.

Add a second heat shrink tube to the one that’s already on the key to make it longer.

Remove the hex-key, spring and screw terminal - these can only be finally fitted after the Z-probe holder is mounted on the effector plate.