GT2 For 10mm Timing Belt,Idler Drive Pulley 20/22/24/25/26/28/30 Tooth 3-12 Bore

Tooth count determines the effective pitch diameter and, combined with your motor pulley, sets your drive ratio. For most 3D printers and light CNC routers, 20T is the standard drive pulley size. Higher tooth counts (24T–30T) are used when you need a larger pitch diameter, reduced belt wrap angle on an idler, or a specific gear ratio in a multi-pulley system. Match the tooth count to your design's geometry requirements.

Most NEMA 17 stepper motors have a 5mm shaft, so Φ5mm is the most common choice for drive pulleys. NEMA 23 motors typically use an 8mm shaft. If you are using an imperial shaft (e.g., ¼" = 6.35mm), select the Φ6.35mm bore variant. Always measure your shaft diameter with calipers before ordering to confirm the correct bore.

Standard variants use one or two set screws to secure the pulley to the shaft. Keyway variants (K3 or K4) include a machined keyway slot that accepts a matching key on the shaft, providing a positive mechanical lock that prevents rotational slipping under higher torque loads. Use keyway variants when set-screw retention is insufficient for your application's torque demands.

Yes. The GT2 and 2GT tooth profiles are functionally identical and fully interchangeable. These pulleys will mesh correctly with any standard GT2 / 2GT timing belt with a 2mm pitch. Ensure the belt width matches — these pulleys are designed for 10mm-wide belts.

These are toothed pulleys intended to engage the belt's tooth profile. When used as an idler, select a bore that fits your idler bolt or bearing shaft. For smooth idler applications (where the belt runs on the outside of a flanged bearing), a different flat idler pulley is typically used. These toothed variants are best suited as driven idlers or tensioners where tooth engagement is desired.

These pulleys are machined from aluminum alloy, which offers a favorable strength-to-weight ratio and natural corrosion resistance in typical indoor environments. For applications exposed to moisture, humidity, or mild chemicals, the natural oxide layer on aluminum provides adequate protection. Avoid prolonged exposure to strong acids or alkalis, which can degrade aluminum surfaces over time.

Each order includes 1 piece. If your project requires multiple pulleys (e.g., a CoreXY printer with two drive pulleys and several idlers), please add the required quantity to your cart or place multiple orders for different size variants as needed.

Before installation, verify that the bore diameter matches your shaft diameter (a snug but not forced fit is ideal), confirm the tooth count matches your belt system's design, and check that the belt width (10mm) matches your existing belt. For keyway variants, ensure your shaft has a matching keyway cut. Tighten set screws (standard variants) against a flat on the motor shaft where possible to prevent slipping.