0.5/1 Mod Pinion Gear 10T-150T Spur Gear with Step 45# Steel Transmission Gear

The module (M) must match the module of the mating gear — a 1M pinion will only mesh correctly with a 1M gear. Tooth count determines your gear ratio: divide the driven gear tooth count by the driving gear tooth count. For example, a 1M 20T pinion driving a 1M 60T spur gear gives a 3:1 reduction. Check your existing gear markings or measure the pitch diameter (PD = module × teeth) to confirm.

Select the bore diameter that matches your shaft diameter exactly. Common motor shaft sizes are 5 mm, 6 mm, 6.35 mm (1/4 inch), 8 mm, and 10 mm. If your shaft has a keyway or flat, you will need to machine the bore accordingly after receiving the gear. Do not select a bore larger than your shaft — a loose fit causes vibration and premature wear.

The Step value is the height of the hub boss that protrudes from the gear face. A 0 mm step means the gear face is flush with no protruding hub. A larger step (e.g., 25 mm or 40 mm) provides a longer shaft engagement surface, useful when you need to position the gear at a specific axial location or when shaft engagement length must exceed the gear face width alone.

These gears are machined from 45# medium-carbon steel, which has a tensile strength of approximately 600–800 MPa depending on heat treatment. They are suitable for moderate-to-high torque applications in robotics, RC drivetrains, and light industrial machinery. For very high-shock or continuous heavy-load environments, consider whether a hardened or alloy steel gear is more appropriate for your specific torque and speed requirements.

45# carbon steel has moderate corrosion resistance. For indoor or dry environments, the bare steel finish is generally adequate with light lubrication. For humid, outdoor, or washdown environments, apply a rust-inhibiting grease or consider a gear with a zinc or black-oxide coating. Contact us to confirm available surface treatment options for your chosen variant.

No. Gears of different modules cannot mesh together — the tooth pitch and profile are incompatible. All gears in a meshing pair must share the same module. Use 0.5M gears exclusively with other 0.5M gears, and 1M gears with other 1M gears. Mixing modules will result in incorrect tooth engagement, noise, and rapid wear.

Module 0.5 gears have smaller, finer teeth suited to compact, lightweight applications such as micro RC cars, small servo mechanisms, and miniature robots. Module 1 gears have larger teeth and can transmit more torque, making them better for larger RC vehicles, 3D printer drives, CNC machines, and light industrial actuators. If replacing an existing gear, measure the pitch diameter and count the teeth to calculate the module: M = PD ÷ T.