The most important thing know is that you do not have to do this yourself.  Mach III will ship the sprocket or pulley you require pre-mounted on the pilot of the clutch, clutch-brake or torque limiter you’ve ordered.  If this is a replacement or new addition to a Mach III unit you already have, we can supply the sprocket or pulley pre-bored and tapped to fit the pilot.  Contact customer service for  pricing and information.

For those who prefer to machine their own sprockets and pulleys:

• Pilot tolerances for Mach III products are ANSI B4.1-1967 (R2004) Class RC 5
• Pilot dimensions for Catalog Products can be obtained from the downloadable detail sheets available from the product pages of this website (click here for an example).
• Pilot dimensions for Non-Catalog Products can be obtained by contacting engineering.
• Consult the Mach III Knowledgebase article Mounting Sprockets and Pulleys on Pilot Style Clutches:  Considerations and Guidelines to avoid problems such as overhung load, inadequate chain clearance and more.