HTD-3M 15-58Teeth Timing Belt Pulley Pitch 3mm AF-typ CNC Drive Wheel Width 11mm

The tooth count determines your drive ratio. Divide the driven pulley teeth by the driving pulley teeth to get the ratio. For a 1:1 ratio on a CNC axis, use matching tooth counts on both ends. For speed reduction (more torque), use a larger tooth count on the driven side. Common CNC router setups use 20 T on the motor and 20 T on the axis for direct drive, while 3D printers often use 16 T or 20 T pulleys on the stepper motor shaft.

NEMA 17 stepper motors typically have a 5 mm output shaft. Select the 5 mm bore variant. If your motor has a flat (D-cut) shaft, the set-screw in the AF-type bore will lock against the flat for a secure, non-slip connection. For NEMA 23 motors with an 8 mm shaft, choose the 8 mm bore variant.

Yes. This pulley is designed for the HTD-3M standard: 3 mm pitch, rounded tooth profile, and 11 mm belt width. It is compatible with any HTD-3M open-ended or closed-loop belt with an 11 mm width. It is not compatible with MXL, GT2, or T5 profile belts, even if the pitch appears similar.

The AF-type set-screw provides adequate holding force for typical CNC and 3D-printer torque levels when properly tightened with the correct hex key. For higher-torque applications (e.g., servo-driven industrial stages), consider using a shaft with a D-flat or adding a second set-screw at 90° if the hub geometry allows. Applying a small amount of thread-locking compound to the set-screw is recommended for vibration-prone environments.

Aluminum alloy offers good natural corrosion resistance in typical indoor workshop and machine environments. The anodized or machined surface resists oxidation under normal operating conditions. For wet or chemically aggressive environments, consider applying a light machine oil to the bore and tooth surfaces. Belt wear is typically the limiting factor in HTD-3M drive systems, not the aluminum pulley itself.

Yes. The AF-type through-bore design works on any shaft within the specified bore diameter range. You can use the same pulley model on both the driving (motor) shaft and the driven shaft, provided the bore matches each shaft diameter. Simply select the appropriate bore variant for each position in your drive system.

Both HTD-3M and GT2 (Gates Tooth 2) use a 3 mm pitch, but the tooth profiles differ. HTD uses a semicircular (rounded) tooth, while GT2 uses a modified curvilinear profile optimized for lower backlash. GT2 belts and pulleys are not interchangeable with HTD-3M components — mixing them will cause poor meshing and accelerated wear. Confirm your belt's tooth profile before ordering.