Touch probe for measuring and digitizing

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This sensor probe draws inspiration from Bertho's work, in addition to other innovators' contributions and patented ideas. It is designed to measure and digitize objects by detecting when the probe touches them. To assemble this device, you will need to print three parts, which can be created using a CNC mill or lathe, as well as two PCB plates that may be crafted by hand if you possess sufficient skill. The steel balls require no soldering, although attaching them can be challenging. This design is intended for use with a hobby CNC mill featuring a 43mm collet mount but can easily be adapted to any type of CNC machine, including 3D printers and measuring rigs mounted in the spindle. Electrical contact is severed as soon as the probe touches anything from any angle. The lower PCB holds the steel balls in place while the upper PCB presses them down, ensuring they remain stationary. The probe holder features three steel pins that rest on pairs of steel balls, creating a single position where all three pins touch the balls. This arrangement forms a loop that is electrically closed only when the pins are in this precise position. Consequently, as soon as the probe is moved even the slightest distance, the circuit opens. Conversely, the circuit closes instantly whenever the probe ceases to make contact with any surface. Based on current observations, a precision of 20 microns (0.02mm) can be achieved, which is more accurate than my CNC can manage. It's possible that your machine may yield even better results. This sensor probe can be utilized in conjunction with my Profiler CNC and Galaad to obtain reliable readings, while Mach3 also supports its functionality. Scanning at a resolution of 0.1mm (plunge probing) yields satisfactory outcomes.