Z-probe with optical switch and Op-amp comparator

myminifactory

An advanced z-probe employs an optical switch and op-amp comparator for enhanced trigger precision. The op-amp, specifically a UA741CN model, draws power from a 5-volt source. A nail measuring 70mmx3mm is carefully cut to the required length to serve as the metallic pin. The neodymium magnet originates from an old DVD drive's optical head, while the spring is salvaged from a ballpoint pen. To integrate the electronics components, a compact perfboard is utilized. A finely polished and precisely trimmed metal pin head is crucial for achieving accuracy in this z-probe. After minimal adjustments, my probe yields the following results: Mean: -0.017500, Min: -0.029, Max: -0.006, Range: 0.023, Standard Deviation: 0.008385. On January 4th, 2019, I designed a dedicated PCB for the z-probe, incorporating an LED to indicate when the probe is active.