0.5 Mod 32 Teeth Spur Gear Transmission Gear With Step Bore 5/6/8mm Motor Gears

Measure your motor shaft diameter with a caliper. This gear is available in 5 mm, 6 mm, and 8 mm step bores. Select the bore that matches your shaft diameter exactly — a step bore is designed to seat at a specific diameter, so an undersized bore will not fit and an oversized bore will produce shaft play. If your shaft is between sizes, choose the smaller bore and consult a machinist for light reaming.

Module (mod) is the metric standard for gear tooth size — it equals the pitch diameter divided by the number of teeth. Two gears mesh correctly only when they share the same module and pressure angle. This gear is 0.5 mod with a 20° pressure angle, so it will mesh with any other 0.5 mod, 20° pressure-angle gear: spur gears, racks, or pinions. It will not mesh correctly with 1.0 mod, 0.8 mod, or imperial diametral-pitch gears.

Yes, for the torque loads typical of small DC motors and stepper motors in the 5–42 mm NEMA frame range. The metal alloy construction handles continuous-duty meshing without the tooth deformation seen in plastic gears. For very high-torque or high-speed applications (above approximately 3,000 RPM under load), verify that the gear's face width and material grade match your torque requirement before committing to a design.

The gear is machined metal and may show surface oxidation over time in humid or wet environments without protective treatment. For indoor workshop, lab, or enclosed enclosure use, no additional treatment is typically needed. For outdoor or high-humidity applications, apply a light machine oil or corrosion-inhibiting grease to the tooth faces and bore as part of your regular maintenance routine.

The step bore is designed for a set-screw or interference-fit attachment method, which is standard for small motor gears in this size class. Ensure your motor shaft has a flat (D-cut) or a drilled set-screw point for a secure, slip-free connection. If your shaft is fully round, a small flat can be filed to provide positive set-screw engagement.

For a single-axis drive or one motor, the 1-piece pack is sufficient. If you are building a multi-axis robot, a 3D printer with dual extruders, or want spares on hand, the 2–5 piece packs offer a lower per-unit cost. The 8 and 10-piece packs are suited for workshop stock, classroom kits, or batch production of small machines where having replacement gears immediately available saves downtime.

Yes. The 0.5 mod, 32-tooth spur gear is a common choice for compact extruder gear trains and small CNC axis reduction stages where a low gear pitch diameter is needed to keep the mechanism compact. Verify that your mating gear (the driven gear on the hobbed bolt or lead screw coupler) is also 0.5 mod and that the center distance between shafts matches the sum of the two pitch radii.