Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
When a mismatched or undersized spur gear causes backlash, slippage, or premature wear in your motion system, the entire machine suffers. Engineers, robotics builders, and CNC hobbyists who need a reliable 1.5 Mod 40-tooth spur gear with a wide bore selection will find this pinion gear a dependable drop-in solution for stepper motor and servo drive assemblies.
This spur gear is machined from 45# medium-carbon steel, offering a solid balance of hardness and machinability. The gear features a module of 1.5 Mod with 40 teeth, available in two teeth thickness options — 12mm (~0.47 in) and 15mm (~0.59 in) — and bore diameters ranging from 6mm to 30mm (~0.24 in to 1.18 in). Select variants include a keyway bore (e.g., 5×2.3mm, 6×2.8mm, 8×3.3mm) for positive torque transmission without set-screw slippage.
Typical applications include stepper motor pinion drives in 3D printers and laser cutters, rack-and-pinion linear actuators for CNC router axes, and gear reduction stages in robotics joints and automated conveyor systems — anywhere a compact, accurately cut 1.5 mod spur gear is required for reliable power transmission.
| Module | 1.5 Mod |
|---|---|
| Number of Teeth | 40T |
| Material | 45# Medium-Carbon Steel |
| Teeth Thickness | 12mm (~0.47 in) or 15mm (~0.59 in) — See variant options |
| Bore Diameter | 6mm – 30mm (~0.24 – 1.18 in) — See variant options |
| Keyway Options | 5×2.3mm / 6×2.8mm / 8×3.3mm (select variants) — See variant options |
| Pitch Diameter | 60mm (~2.36 in) [calculated: Module × Teeth = 1.5 × 40] |
| Pressure Angle | 20° (standard) |
| Gear Type | Spur Gear (straight tooth) |
| Finish | See variant options |
| Compatible Module | 1.5 Mod mating gears and racks |
Measure your motor shaft diameter with a caliper. Common NEMA 17 stepper shafts are 5mm; NEMA 23 shafts are typically 6.35mm or 8mm; larger servo motors may use 10mm, 12mm, or larger. Select the bore that matches your shaft diameter exactly. If your shaft has a flat or keyway, choose a keyway bore variant for a positive mechanical lock.
Plain bore variants use a set screw to secure the gear to the shaft — suitable for lighter loads and applications where disassembly is frequent. Keyway bore variants (5×2.3mm, 6×2.8mm, 8×3.3mm) use a machined slot and key to transmit torque directly, preventing rotational slip under high torque or reversing loads. For CNC drives and robotics joints, keyway variants are generally recommended.
45# medium-carbon steel offers a tensile strength typically in the range of 600–800 MPa after standard heat treatment, making it well-suited for moderate-to-high load spur gear applications such as CNC axis drives, 3D printer extruder gears, and light industrial automation. For very high-speed or heavy-shock-load environments, consider whether a hardened or alloy steel gear would be more appropriate for your specific duty cycle.
45# steel has moderate corrosion resistance. In typical indoor workshop or machine enclosure environments, the gear will perform reliably. For humid, wet, or chemically exposed environments, applying a light machine oil or grease to the gear teeth is recommended to prevent surface oxidation and extend service life.
This gear is cut to 1.5 Module (Mod 1.5) with a standard 20° pressure angle. It will mesh correctly with any other 1.5 Mod spur gear, pinion, or rack with the same module and pressure angle. Do not attempt to mesh with gears of a different module — tooth profiles will not be compatible.
Choose 12mm teeth thickness for compact assemblies where axial space is limited, such as small CNC routers or 3D printer drives. Choose 15mm teeth thickness when you need greater face width engagement for higher torque capacity or when your mating rack or gear is 15mm wide. When in doubt, 15mm provides more contact area and generally handles higher loads.
Yes. The bore range (6–30mm) covers many servo motor output shaft diameters. Verify your servo shaft diameter and whether it has a keyway. Select the matching bore and keyway variant accordingly. The 1.5 Mod tooth profile is independent of the motor type — what matters is matching the module to your mating gear or rack.
