GT2 6 10mm Timing Belt Idler Pulleys 16-60 Teeth 3-15mm Bore For 3D Printer CNC

Use a smooth idler when the pulley contacts the back (flat side) of the belt — this is the most common idler configuration in CoreXY and Cartesian 3D printers. Use a toothed idler when the pulley contacts the toothed face of the belt and you need positive engagement to prevent belt slip or to change belt direction while maintaining tooth mesh.

Tooth count determines the pulley's outer diameter. Smaller counts (16 T–20 T) suit tight belt paths with limited space; larger counts (40 T–60 T) are used for longer belt spans or where a larger wrap angle is needed to reduce belt stress. Check your printer or router's BOM or frame drawings for the specified idler tooth count before ordering.

Measure your idler shaft or bolt diameter with a caliper. Common sizes in 3D printers are 3 mm (M3 bolt), 4 mm (M4 bolt), and 5 mm (M5 bolt). CNC and larger DIY builds often use 6 mm, 8 mm, or 10 mm shafts. Select the bore that matches your shaft diameter — a bore that is too large will cause wobble and belt tracking issues.

Yes. These pulleys conform to the GT2 2 mm pitch profile, which is an open standard. They are compatible with GT2 timing belts from any manufacturer as long as the belt width matches the rim width you select (6 mm belt → 7 mm rim variant; 10 mm belt → 11 mm rim variant).

The 7 mm rim is designed for standard 6 mm wide GT2 belts used in most desktop 3D printers (e.g., Ender, Voron, RatRig). The 11 mm rim accommodates wider 10 mm GT2 belts, which are common in heavier-duty CNC routers and high-speed CoreXY builds that require greater belt load capacity.

Bearing inclusion varies by variant. Please check the product images and variant description carefully. Many GT2 idler pulleys in this range are designed to be mounted on a bolt with a separate bearing (e.g., 625ZZ or 624ZZ) that you install yourself. If your application requires a pre-assembled bearing idler, confirm the specific variant before purchasing.

Yes. These GT2 idler pulleys are suitable for any application that uses GT2 2 mm pitch timing belts, including laser engravers, pick-and-place machines, and custom linear-motion rigs. Ensure the bore size matches your shaft and the rim width matches your belt width for reliable operation.