Precision Brand 56509 Mill Key Stock 3/4 X 3/4 X 12 in

Product Description

The PRECISION BRAND 56509 is a mill key stock bar used to transmit torque between shafts and hubs in mechanical power-transmission assemblies. Cut from low-carbon steel with a plain mill finish, it measures 0.75 inches high by 0.75 inches wide by 12 inches long and is sold as a single piece. Machinists, millwrights, and maintenance technicians use this stock when fabricating or replacing keys in pulleys, gears, sprockets, and couplings. The square cross-section profile suits standard keyway configurations that call for 3/4-inch key stock.

This key stock is appropriate for general industrial and commercial maintenance applications where a standard square mill key profile is required. It can be cut to a custom length on a bandsaw or milling machine to fit a specific shaft and hub assembly. Typical uses include OEM fabrication, field repair of rotating equipment, and preventive maintenance on conveyor drives, pump shafts, and fan assemblies. It is stocked as a 12-inch bar to allow multiple keys to be produced from a single piece.

Key Features

• Square 0.75-inch by 0.75-inch cross section fits standard 3/4-inch keyway slots
• Low-carbon steel construction provides adequate shear strength for general power-transmission service
• Plain mill finish allows for easy marking, cutting, and fitting without surface treatment removal
• 12-inch length yields multiple finished keys per bar, reducing material waste
• Single-piece packaging suits jobsite and shop use without excess inventory

Compatibility

Designed as a standard-dimension mill key stock for use in any 3/4-inch square keyway application across general industrial, commercial, and maintenance power-transmission assemblies.

Installation Notes

Installation is typically performed by a machinist or millwright. De-energize and lock out the machine before removing or installing any key. Cut the key stock to the required length using a bandsaw, cold saw, or milling machine, then deburr all edges before fitting. Verify keyway and key dimensions with calipers before final assembly to ensure proper fit and torque transmission.