Module 1.5 Spur Gear A2 Steel 12-32 Tooth with Hub Pinion Motor Gear Bore 6-20mm

Tooth count determines your gear ratio. Divide the driven gear teeth by the driving gear teeth to get the ratio. For example, a 30-tooth gear driven by a 15-tooth pinion gives a 2:1 reduction. Match the module (1.5) on both gears — mismatched modules will not mesh correctly.

Measure your motor shaft diameter precisely with calipers. Common NEMA 17 stepper shafts are 5 mm, NEMA 23 are typically 6.35 mm or 8 mm, and larger motors may use 10–14 mm shafts. Select the bore that matches your shaft, or the next size up if you plan to use a set screw or loctite for adjustment. For positive locking, choose a keyway variant where available.

A2 stainless steel work-hardens under load, giving it good fatigue resistance for light-to-medium duty cycles. Module 1.5 gears are suited for low-to-moderate torque applications such as desktop CNC axis drives, robotic joint reduction stages, and small conveyor feeds. For heavy industrial loads or continuous high-speed operation, consult a mechanical engineer for load calculations.

A2 stainless steel offers good corrosion resistance in most indoor and mildly humid environments. It is not recommended for prolonged immersion in saltwater or highly acidic conditions. For outdoor or wet environments, periodic lubrication with a compatible gear grease will extend service life.

Plain bore gears (6–12 mm) rely on set screws or adhesive for shaft retention and are easier to install and reposition. Keyway bore gears (12–20 mm) include a machined slot that accepts a matching key on the shaft, providing positive rotational locking and eliminating slip under reversing or shock loads. Keyway variants are recommended for higher-torque or direction-reversing applications.

Yes — this gear will mesh correctly with any standard Module 1.5 rack (for linear motion) or a compatible M1.5 pinion. It is not compatible with worm gears, which use a different tooth geometry. Always verify that the mating component is also rated Module 1.5 before assembly.

For a standard spur gear, the pitch diameter equals Module × Teeth (e.g., 1.5 × 20 = 30 mm pitch diameter). The outer diameter (addendum circle) is approximately pitch diameter + 2 × Module (e.g., 30 + 3 = 33 mm for a 20-tooth gear). Use this formula to verify clearance in your assembly before ordering.