Zero Probe

This is a very simple but *very* sensitive normally closed (NC) touch probe. When the tip is moved by any amount it opens the switch contacts.

You should be able to find the parts that aren't printed in your toolbox or spare parts box.

Parts not printed
>Screw with a flat (not countersunk) shoulder 3.3mm diameter and a smooth shank longer than 18mm. Mine was from a PC heatsink

>Washer that fits the screw loosely but has an OD of 9.4mm

>Coil spring 4mm OD and about 10mm long (extended). Mine came out of a squirt bottle trigger/pump

If you don't have these parts it is easy to find similar things to fit, like using a pop-rivet head or a 3.3mm rod and glue a nut to make the head.

I have included .stp files so you can adapt the parts you have to work for this design. Failing that, these are very easy to design, even in Tinkercad and its really only the "Guide" that will need to be changed.

If you have something very close in size but too big, PLA will easily soften i