Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Engineers and makers who rely on repeatable, low-backlash motion know the frustration of pulleys that slip, wobble, or arrive with bore tolerances that force rework. These S2M 10mm timing belt drive pulleys are machined for builders who need a drop-in fit the first time — whether you are designing a desktop CNC router, a pick-and-place machine, or a custom robotic arm.
Each pulley is machined from aluminum alloy with a smooth-tooth S2M profile and a 10mm belt width. Tooth counts span 70T, 72T, 74T, 75T, 76T, 78T, and 80T. Bore diameters range from 5mm to 25mm (approximately 0.197" to 0.984"), with a stepped hub for axial positioning. Keyway options (3mm, 4mm, 5mm, 6mm, or 8mm) are available on select bore sizes for positive torque transmission without set-screw dependency.
Typical use cases include S2M belt-driven linear stages where consistent pitch diameter matters, multi-axis CNC gantry systems requiring matched pulley sets, and light-duty conveyor or indexing mechanisms where a 2mm pitch S2M belt is already specified. The stepped hub design also suits applications where the pulley must be located against a shoulder on the shaft.
| Belt Profile | S2M (2mm pitch, smooth tooth) |
|---|---|
| Belt Width | 10mm |
| Number of Teeth | 70T, 72T, 74T, 75T, 76T, 78T, 80T |
| Bore Diameter | 5mm, 6mm, 6.35mm, 8mm, 10mm, 12mm, 12.7mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 25mm |
| Keyway Width | Without keyway, 3mm, 4mm, 5mm, 6mm, 8mm (see variant options) |
| Hub Style | Stepped hub |
| Material | Aluminum alloy |
| Finish | See variant options |
| Flange | See variant options |
| Outside Diameter | See variant options |
| Hub Length | See variant options |
The tooth count determines the pitch diameter of the pulley, which directly sets your drive ratio when paired with a specific belt length and a second pulley. Higher tooth counts (e.g., 80T) give a larger pitch diameter and a lower reduction ratio when paired with a smaller driver pulley. Use the formula: ratio = driven teeth ÷ driver teeth. For most CNC gantry and linear stage builds, matching tooth counts on both ends gives a 1:1 ratio for direct-drive configurations.
Measure your motor shaft diameter with calipers before ordering. Common NEMA 17 stepper shafts are 5mm; NEMA 23 shafts are typically 6.35mm (1/4") or 8mm; larger servo motors often use 10mm, 12mm, or larger shafts. Select the bore that matches your shaft diameter exactly — these pulleys are machined to close tolerances and are not intended to be bored out after purchase.
A keyway is recommended for applications with significant torque, reversing loads, or where set-screw-only retention has proven unreliable. The keyway width must match the key stock on your shaft. Standard metric key widths for common bore sizes: 8mm bore → 3mm key; 10mm bore → 3mm or 4mm key; 12mm bore → 4mm key; 14–15mm bore → 5mm key; 18–19mm bore → 6mm key; 25mm bore → 8mm key. Confirm against your shaft specification before ordering.
Yes — these pulleys are designed for standard S2M synchronous belts with a 2mm pitch and 10mm width. They are not compatible with GT2, HTD, or other belt profiles, even if the pitch appears similar. Always verify the belt profile designation (S2M) on your belt before pairing it with these pulleys.
Aluminum alloy pulleys are well-suited for light-to-medium duty CNC, 3D printing, robotics, and automation applications where belt tension is moderate and operating temperatures are within normal ambient ranges. For heavy industrial drives with sustained high belt tension or shock loads, steel pulleys may be more appropriate. For the vast majority of hobbyist and professional maker applications these aluminum pulleys are the standard choice due to their lower inertia and ease of machining for custom modifications.
Aluminum alloy naturally forms a thin oxide layer that provides moderate corrosion resistance in typical indoor environments. For applications exposed to moisture, cutting fluids, or outdoor conditions, consider applying a light coat of dry lubricant or anodizing the pulley surface. These pulleys are not recommended for submerged or highly corrosive chemical environments without additional surface treatment.
These pulleys use the S2M profile (2mm pitch), which is distinct from the GT2 profile commonly used in consumer 3D printers. If your printer or laser cutter uses S2M belts specifically, these pulleys are compatible. If your machine uses GT2 belts, these pulleys will not mesh correctly. Check your belt profile before purchasing.
