GT2 20T Toothless Idler Pulley W6 B5

Keep your belt-driven motion system running smoothly with this GT2 Idler Pulley, a toothless (smooth) version of the standard 20-tooth GT2 pulley sized for 6mm-wide timing belts. Since idler pulleys don’t drive the belt, this smooth-surfaced design is purpose-built for the return or tension side of a GT2 belt loop, where it guides the belt without engaging its teeth.

Machined from lightweight aluminum alloy with a corrosion-resistant surface finish, this idler pulley features a 5mm bore fitted with dual motor-grade bearings for smooth, low-friction rotation. The smooth outer surface eliminates tooth-to-tooth contact on the non-driven side of the belt, reducing wear and helping maintain consistent belt tension and alignment throughout the travel of your axis. Its dual-flanged profile keeps the belt centered even during fast direction changes, preventing it from walking off the pulley during operation.

This idler pulley is a common component in 3D printer X/Y axis assemblies, CNC routers, and other GT2 belt-driven motion systems, typically paired with a toothed drive pulley on the motor shaft. Its 5mm bore fits directly onto smooth rods, shafts, or mounting screws used in most hobbyist printer and CNC frame designs, making it a straightforward drop-in replacement or upgrade part for belt tensioning setups.

Specification:

• Pulley Type : GT2 Idler (Toothless / Smooth)
• Tooth Size Reference : 20T Equivalent
• Pitch : 2mm
• Bore Diameter (B) : 5mm
• Belt Width (W) : 6mm
• Material : Aluminum Alloy
• Bearing : Dual Motor-Grade Bearings