CNC Machined NEMA 23 Motor Mount | 6061 Aluminium, 3-Axis, Design for Machining

Belt-tension motor mount for a NEMA 23 stepper, designed to be machined from one block of 6061-T6 aluminium. I designed it around the tools and setups a normal job shop already has. It needs three setups on a 3-axis mill: bottom face first as datum A, then everything reachable from the top (walls, gussets, weight-relief pocket, tension slots, M4 accessory holes), then the front face for the pilot bore and motor taps. There is no 4th axis and no special tooling. Every inside corner is sized to a standard end mill: R6 in the pocket for a Ø10 cutter and R3 at the gusset roots for Ø6. The NEMA 23 pilot is Ø38.10 H8, square to the motor face within 0.02, with 4x M5 on the 47.14 mm square and 1.8 d of thread in the plate. Four M6 counterbored slots give 6 mm of belt tension travel along the belt line. The thinnest wall is 3.5 mm. The finished part weighs about 500 g. The STEP includes the motor, a GT2 20T pulley and all eight screws, so fit can be checked before cutting metal. Delivered: STEP assembly, machinist-ready STEP of the part (tapped holes at tap-drill size, threads called out), a setup map with every face coloured by operation, and renders.