1/1.5 Mod 12T-150T Spur Gear 45# Steel Pinion Gear Thickness 1M-10mm 1.5M-15mm

Module (Mod) defines the tooth size and pitch diameter. Mod 1 teeth are smaller and suit lighter loads or compact drives; Mod 1.5 teeth are larger and handle moderately higher torque. Both modules must match across all meshing gears in your drive — you cannot mix Mod 1 and Mod 1.5 gears in the same mesh.

Divide the driven gear tooth count by the driving gear tooth count to get the reduction ratio. For example, pairing a 20T pinion with a 60T gear gives a 3:1 reduction. This listing covers 12T to 150T, so you can achieve ratios from approximately 1:1 up to 12.5:1 using gears from this range alone.

The gears are machined from 45# medium-carbon steel, which typically has a tensile strength of 600–800 MPa in the as-machined condition. They are well-suited for light-to-medium duty applications such as CNC axis drives, robotics, and motorized hobby projects. For heavy industrial loads or continuous high-speed operation, consider heat-treated or alloy-steel alternatives.

45# steel has moderate corrosion resistance. For indoor or dry environments, the bare steel finish is adequate with periodic light oiling. For humid or outdoor use, apply a rust-inhibiting grease or consider a zinc-plated or stainless-steel gear instead.

Bore diameter varies by tooth count and module — please check the variant detail or contact us to confirm the exact bore for your chosen size. The bore can be enlarged or a keyway added using standard lathe or milling operations. Avoid removing more than 30–40% of the hub wall thickness to maintain structural integrity.

Yes — these gears use standard involute tooth geometry and will mesh correctly with any Mod 1 or Mod 1.5 rack, respectively. They are not designed to mesh with worm gears, which require a different helix angle and tooth form. For rack-and-pinion linear drives, simply match the module of the rack to the module of the gear you select.

Measure the outer diameter (OD) of the existing gear in mm. For a Mod 1 gear: OD ≈ (T + 2) × 1 mm. For a Mod 1.5 gear: OD ≈ (T + 2) × 1.5 mm. Solve for T (tooth count), then select the matching variant. Alternatively, count the teeth directly on the worn gear and match the module by measuring the tooth pitch.