3M Zahnrad Riemenscheibe 18- 46 Zähne BF-Typ Pulley - für 10mm Breite Zahnriemen

Tooth count determines the pitch circle diameter and therefore the drive ratio. Smaller tooth counts (18Z–25Z) give more torque at lower speeds; larger counts (36Z–46Z) suit higher-speed, lower-torque applications. Match the tooth count to your belt length and center distance calculation. For CNC axes, 20Z is a common starting point with 3M belts.

BF stands for Flanged Bore — the pulley has raised flanges on both sides of the tooth profile. These flanges prevent the timing belt from walking off the pulley laterally, which is especially important in open-loop or lightly tensioned systems like 3D printers and light CNC machines.

A plain bore (e.g., "8") is a smooth cylindrical hole — the pulley is typically secured with a set screw. A keyway bore (e.g., "8K3") has a machined slot that accepts a matching key on the shaft, providing positive rotational locking and eliminating set-screw slip under reversing loads. The number after "K" indicates the keyway width in mm (K3 = 3mm key, K4 = 4mm key, etc.).

Yes. These pulleys are designed for 3M pitch timing belts (3mm tooth pitch, 10mm wide). They are compatible with standard 3M open-end and closed-loop timing belts. Always verify the belt tooth profile (trapezoidal vs. curvilinear) matches your belt — most 3M belts used in DIY automation are trapezoidal pitch.

Use a digital caliper to measure the outer diameter of your motor or drive shaft. Select the bore size that matches — for example, a NEMA 17 stepper motor typically has a 5mm shaft (select bore "5"), while a NEMA 23 often uses an 8mm shaft (select bore "8" or "8K3" for keyway). For metric shafts with keyways, match both the shaft diameter and keyway width to the K-suffix variant.

These pulleys are machined from aluminum alloy, which offers a good strength-to-weight ratio and natural corrosion resistance in typical indoor environments. For humid or outdoor applications, an anodized finish provides additional protection. Avoid prolonged exposure to strong acids or salt spray without additional coating.

Yes. 3M pitch pulleys are widely used in larger-format 3D printers and CNC routers. For standard desktop FDM printers using GT2 belts, note that GT2 uses a 2mm pitch — ensure your printer uses 3M belts before ordering. These are ideal for custom builds, Voron-style machines adapted for 3M belts, or direct-drive extruder systems.