Nema17 stepper housing with power connector and hall ref point.

thingiverse

This Fischertechnik Nema17 stepper motor housing is specifically designed for use with Fischertechnik blocks, making it easy to integrate into existing projects. To facilitate connectivity, the housing includes built-in connectors for motor wires and an additional three-pin connector for hall reference point detection. This setup allows for seamless motor connection and simplifies the process of setting a zero point after power-up. The hall detector is seamlessly integrated into the housing, utilizing a Neodym magnet D2x3mm located within the shaft adaptor to provide the necessary signal. The adaptor itself features an output to the standard 4mm Fischertechnik shaft, ensuring compatibility with various components. The Nema17 motor boasts a 5mm shaft diameter, which requires finishing with a drill after 3D printing - an 18mm deep bore is necessary for smooth operation. The shaft adaptor not only mounts FT gears but also offers flexibility in terms of mounting options: users can choose between three 4mm holes or three M4 tapped holes, depending on their specific requirements. When drilling the 3 holes tapped with M4, it's recommended to use a small electric hand drill machine at low speed to achieve precise results and avoid damaging the material. The adaptor is securely fixed to the 5mm shaft using an M4 screw, which also needs to be made by the user. Inside the adaptor, there's a small bore for a Neodym magnet D2x3mm, requiring drilling with D1.9mm and then D2.0mm to a depth of 1.5mm. When pressing the magnet in place, ensure you pay attention to its polarity, as the hall detector AH3144 is unipolar and won't function correctly if polarized incorrectly. If necessary, you can remove the magnet and reverse it. To connect the wires to the three-pin connector, arrange them according to a servo motor configuration: GND, VCC, OUT. Feel free to adjust the connection as needed, ensuring correct hardware compatibility. The hall AH3144 detector is internally protected against incorrect polarization, but if polarized incorrectly, it may not always work. On the adaptor, you can screw on gears like 30T or 40T, or even attach a FT wheel FI-31019. If using the hall detector, make sure no screws protrude from the bottom by utilizing the M4 holes that allow the screw heads to be positioned on the opposite side. The included photos provide a clear visual representation of this setup.