Boneham SF328EX Slip-fixed Drill Bushing 0.159 in Id Steel

Product Description

The BONEHAM SF328EX is a slip-fixed drill bushing designed for precision hole-location applications in jig and fixture work. It features an inside diameter of 0.159 inches (No. 21 wire gauge) with a tolerance of +0.0001 to +0.0004 inches, a body outside diameter of 0.500 inches, and a length under head of 0.500 inches. Manufactured from steel with a hardness rating of 60 to 65 HRC, the SF328EX provides consistent bore accuracy and wear resistance through high-cycle drilling operations. Machinists, toolmakers, and fixture builders install this bushing where renewable guidance is required without full liner removal.

The SF328EX fits standard jig and fixture assemblies that call for an SF-series slip-fixed bushing per ANSI standards. The slip-fixed design allows the bushing to be removed and replaced without disturbing the liner bushing already installed in the jig plate, making it well suited for multi-operation setups where different drill sizes are needed at the same hole location. The head-type configuration and LS-1 compatible lock screw retain the bushing securely during operation.

Key Features

• SF-series slip-fixed design allows bushing replacement without liner removal
• Inside diameter of 0.159 inches (No. 21 drill size) with +0.0001 to +0.0004 inch tolerance
• Body outside diameter of 0.500 inches, length under head of 0.500 inches
• Steel construction hardened to 60 to 65 HRC for long service life
• Head outside diameter of 51/64 inches, head height of 1/4 inch
• LS-1 compatible lock screw seat for positive retention in the liner
• Renewable bushing — replaces without machining the jig plate

Compatibility

Designed for use with standard liner bushings and jig plates requiring an SF-series slip-fixed bushing. Accepts LS-1 lock screws. Conforms to ANSI bushing standards for SF-type drill bushings.

Installation Notes

Installation is performed by toolmakers or machinists working with drill jig assemblies. Ensure the liner bushing bore and the jig plate are free of chips and burrs before seating the SF328EX. The lock screw must be engaged to prevent rotation or withdrawal during drilling. Do not press or hammer the slip-fixed bushing into the liner — it is designed to slip in and out by hand with the lock screw released.