Spur Gears Pinion Gear 1 Mod Transmission Gear With Step 12T-59T Teeth 45# Steel

Select the tooth count based on your required gear ratio and available center distance. For a rack-and-pinion drive, smaller tooth counts (12T–20T) give finer linear resolution per motor revolution. For reduction gearboxes, pair a small pinion with a larger driven gear — for example, a 15T pinion meshing with a 45T gear gives a 3:1 reduction. Use the outside diameter values listed in the variant options to calculate center distance.

These gears are machined from 45# medium-carbon steel, which is suited to moderate-load, low-to-medium speed transmission applications typical of CNC machines, robotics, and light industrial equipment. For heavy-duty or high-cycle applications, consider hardened or alloy steel gears. Exact load ratings depend on operating speed, lubrication, and mounting — consult a gear design reference for your specific duty cycle.

45# carbon steel has moderate corrosion resistance. For indoor, dry environments these gears perform well with periodic light lubrication. For humid, outdoor, or washdown environments, apply a corrosion-inhibiting grease or consider stainless steel alternatives. The stepped hub area is particularly important to keep lubricated if the gear is press-fit or retained with a set screw.

Yes — any gear or rack with a Module 1 (Mod 1) tooth profile and a standard 20° pressure angle will mesh correctly with these pinions. Verify the module and pressure angle of your existing components before ordering. These gears are not compatible with Module 0.5, Module 1.5, or other non-Mod-1 profiles.

Bore diameter varies by tooth count and is listed in the variant detail or product images. Measure your shaft diameter with calipers before selecting a variant. If the bore is slightly undersized, it can typically be bored or reamed to the required diameter by a machine shop. Do not force-fit a gear onto an oversized shaft as this can crack the hub.

Yes — each tooth count is available in a 1-piece pack, making it straightforward to order a single gear for prototype validation before committing to a 3, 5, or 10-piece quantity. Select "1 Pcs" in the Packing Quantity option when adding to cart.

The stepped hub on these gears includes a reduced-diameter shoulder section that acts as an axial stop when the gear is mounted on a shaft. This makes it easier to position the gear consistently without measuring from a reference face each time. Plain hub gears lack this feature and require a separate collar or spacer to achieve the same axial positioning.