Boneham SF3212HG Slip-fixed Drill Bushing 1/4 in Id Steel

Product Description

The BONEHAM SF3212HG is a slip-fixed drill bushing designed to guide cutting tools with precision in jig and fixture applications. Built to ANSI standards, this SF-series bushing features a 1/4 inch inside diameter (0.2500 inches decimal) and a 1/2 inch body outside diameter (0.5000 inches decimal). The steel construction is hardened to 60 to 65 HRC, providing the wear resistance required for repeated drilling, reaming, or boring operations. The head-style design and slip-fixed installation method allow the bushing to be seated and locked in a liner bushing without permanent press-fit installation, making tool changes faster in production environments. Licensed machinists, tool and die makers, and fixture builders are the primary installers.

This bushing is suited for use in drill jigs and machining fixtures across manufacturing, metalworking, and production environments. The SF designation identifies it as a slip-fixed type per industry standards, meaning it is intended to slip into a fixed liner bushing and be locked in position with a compatible lock screw. The LS-1 lock screw compatibility is specified for this part. Typical applications include guiding twist drills, reamers, or counterbores in repetitive-cycle machining setups where bushing replacement during a job run is required.

Key Features

• Inside diameter of 1/4 inch (0.2500 inches) with tight tolerance of +0.0001 to +0.0004 inches for accurate tool guidance
• Steel construction hardened to 60 to 65 HRC for extended wear life in high-cycle drilling operations
• Head-style body with head outside diameter of 51/64 inch and head height of 1/4 inch for positive seating in liner
• 3/4 inch length under head accommodates standard fixture plate thicknesses
• Compatible with LS-1 lock screw for secure positioning in slip-fixed liner bushings
• Renewable bushing design allows field replacement without disturbing the liner or fixture plate

Compatibility

Designed for use with LS-1 compatible lock screws in standard slip-fixed liner bushing systems per ANSI specifications. The SF industry code designates compatibility with fixed liner bushings of the corresponding nominal size.

Installation Notes

Installation is performed by qualified machinists or toolmakers as part of drill jig setup or fixture maintenance. The bushing slips into an installed fixed liner bushing and is secured with an LS-1 lock screw — do not force-fit or hammer the bushing into a non-liner bore, as this can damage the seating surfaces. Verify that the liner bushing bore and the SF3212HG outside diameter are clean and free of chips before installation. Follow applicable shop safety and lockout procedures when servicing fixtures on active machinery.