Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
When your motion-control build demands consistent belt alignment and zero slippage, a poorly fitted pulley becomes the weakest link. Engineers, makers, and automation integrators working on CNC routers, 3D printers, laser cutters, and conveyor systems need a pulley that locks firmly to the shaft and keeps the belt seated under load — every cycle, every time.
These aluminium V-groove pulleys feature a machined 6061-series aluminium body with a clean V-profile groove sized for 5 mm or 6 mm wide belts. Outer diameters span 20 mm to 100 mm (approximately 0.79 in to 3.94 in), and bore sizes range from 5 mm to 25 mm (approximately 0.20 in to 0.98 in) to suit a wide variety of motor and idler shaft diameters. Each pulley ships with a radial set screw that clamps directly onto the shaft for a secure, tool-adjustable fit.
Typical use cases include open-loop belt-drive axes on desktop CNC mills, tensioner idler assemblies in 3D printer CoreXY kinematics, and lightweight conveyor drive stations in small-batch automation rigs. The aluminium construction keeps rotating mass low — a key factor in high-acceleration stepper and servo applications where inertia directly affects positioning accuracy.
Choose the exact drive ratio you need. OD options from 20 mm (0.79 in) to 100 mm (3.94 in) let you dial in speed reduction or 1:1 drive without custom machining.
A radial set screw is pre-installed in each pulley hub. Tighten with a standard hex key to lock the pulley onto the shaft — no adhesive, no press-fit tools required.
Lightweight yet rigid aluminium construction reduces rotational inertia for faster acceleration in stepper and servo-driven axes while resisting deformation under belt tension.
The groove geometry is machined to maintain consistent belt contact and lateral tracking, minimising belt wander and reducing wear on both the belt and pulley flanks.
Bore options from 5 mm to 25 mm cover common motor shaft diameters used in NEMA 17, NEMA 23, and equivalent servo motors, as well as idler rod diameters.
Groove width is matched to 5 mm and 6 mm belts — the two most common widths in desktop CNC and 3D printer motion systems — so no modification is needed out of the box.
| Material | Aluminium alloy (6061-series) |
|---|---|
| Outer Diameter (OD) | 20 mm / 30 mm / 40 mm / 50 mm / 60 mm / 80 mm / 100 mm |
| Bore Diameter | See variant options (5 mm – 25 mm) |
| Compatible Belt Width | 5 mm, 6 mm |
| Groove Profile | V-groove |
| Retention Method | Radial set screw (hex key drive) |
| Finish | Natural machined aluminium |
| Weight | See variant options |
| Quantity per Order | 1 pcs |
The outer diameter determines your drive ratio when paired with a motor pulley. A larger driven pulley relative to the drive pulley reduces output speed and increases torque. For 1:1 drives (e.g., idler or direct-drive setups), match the OD to your existing pulley. For speed reduction, divide the driven OD by the drive OD to get the ratio. Select from 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, 80 mm, or 100 mm to suit your geometry.
Measure your shaft diameter with a calliper before ordering. The bore must match the shaft diameter closely — a loose bore will cause runout even with the set screw tightened. Available bores range from 5 mm to 25 mm depending on the OD selected. Check the variant dropdown for bore options available for your chosen OD.
The radial set screw provides firm clamping for typical belt-drive loads encountered in CNC routing, 3D printing, and light conveyor applications. For shafts with a flat (D-cut), align the set screw to the flat for maximum retention. For round shafts, ensure the screw is fully seated and apply thread-locking compound if vibration is a concern.
This pulley features a smooth V-groove profile designed for V-belts and round belts up to 6 mm wide. It is not toothed and is not compatible with GT2, HTD, or other synchronous timing belts that require a matching tooth profile. For synchronous drives, a toothed timing pulley is required.
6061-series aluminium has good natural oxidation resistance suitable for indoor workshop and light industrial environments. For humid or outdoor environments, consider applying a light coat of machine oil or clear lacquer to the exposed surfaces. The natural machined finish does not include anodising unless stated in the variant listing.
Yes. The pulley can be mounted on a fixed rod or bolt acting as an idler axle, provided the bore matches the rod diameter. In idler configurations, the set screw can be left loose to allow free rotation, or tightened if the rod itself rotates. Adding a flanged bearing inside the bore is recommended for high-speed idler use to reduce friction and wear.
The set screw typically uses a standard M3 or M4 hex socket drive depending on the pulley size. A 1.5 mm or 2 mm hex key (Allen key) is commonly required. If a specific size is critical for your build, contact us to confirm the set screw specification for your chosen variant before ordering.
