1 Mod 44-47 Teeth Spur Gear Transmission Gear With Step 45# Steel Motor Gears

The tooth count determines your gear ratio when paired with a pinion. Divide the driven gear teeth by the driving gear teeth to get the ratio. For example, a 44T gear driven by an 11T pinion gives a 4:1 reduction. Choose a higher tooth count for more torque and lower output speed, or a lower count for higher speed. All four options share the same Module 1 pitch, so they mesh with any 1M mating gear.

Measure your motor or gearbox output shaft diameter with a caliper. Select the bore that matches your shaft diameter exactly. If your shaft has a keyway, choose a bore option that includes the matching keyway dimensions (e.g., 5×2.3 mm for a 14 mm keyed shaft). If you need the gear to sit flush against a motor face, select a step-bore variant with the appropriate step length (25 mm, 35 mm, or 38 mm).

A standard round bore is a plain cylindrical hole — suitable for press-fit or set-screw retention. A keyway bore adds a rectangular slot that mates with a key on the shaft, preventing rotational slippage under torque. A step bore has a larger-diameter shoulder machined into one face of the gear hub, allowing the gear to register against a motor flange or bearing housing for precise axial positioning without additional spacers.

45# carbon steel offers a good balance of machinability and tensile strength (typically 600–800 MPa tensile), making it suitable for most general-purpose motor drive applications. 304 stainless steel has similar or slightly lower hardness but significantly better corrosion resistance, ideal for food-adjacent, marine, or humid environments. Blue nylon gears are much lighter and run quietly without lubrication, but are suited to lower-torque, lower-speed applications where noise reduction matters more than peak load capacity.

Yes. All gears in this listing conform to the Module 1 (1M) metric standard with a 20° pressure angle. They will mesh correctly with any other 1M external spur gear, 1M rack, or 1M pinion regardless of brand, as long as the mating gear also uses the same module and pressure angle. Do not mix with imperial DP (diametral pitch) gears — they are not interchangeable.

For steel-on-steel meshing (both 45# and stainless steel gears), light lubrication with gear grease or oil is recommended to reduce wear and extend service life, especially at higher speeds or loads. Nylon gears can typically run dry at moderate speeds and loads. Always consult your application's load and speed requirements when deciding on a lubrication schedule.

For outdoor or wet environments, select the 304 Stainless Steel bore option. 45# carbon steel gears will rust if exposed to moisture without protective coating or regular lubrication. Blue nylon gears are inherently corrosion-resistant but may absorb moisture over time, which can slightly affect dimensional tolerances. For fully weatherproof builds, stainless steel is the recommended choice.

The 1-piece option is ideal for prototyping, single-axis builds, or replacement of a single worn gear. The 4-piece pack offers a lower per-unit cost and is suited for multi-axis machines (e.g., XYZ gantries), production runs, or keeping spares on hand. Both packs ship the same gear model and bore specification — only the quantity differs.