Boneham H3212GK Press Fit Headed Drill Bushing

Product Description

The BONEHAM H3212GK is a Type H press fit headed drill bushing designed to guide cutting tools with precision during drilling operations. Manufactured from steel, this bushing features an inside diameter of 0.209 inches (wire size #4) with a tight tolerance of +0.0001 to +0.0004 inches, ensuring accurate hole location and consistent repeatability across production runs. With a body outside diameter of 0.5 inches and a length under head of 0.75 inches, it installs directly into a jig plate or fixture body without a locking mechanism. Machinists, tool and die makers, and fixture builders specify this style for permanent, non-renewable installations where the bushing stays in place for the life of the fixture.

Type H headed drill bushings like the H3212GK are used in drill jigs, machining fixtures, and production tooling setups where a positive head stop is required to control the installed depth of the bushing. The head bears against the top surface of the jig plate, providing a flush or slightly proud seating reference. This configuration is common in high-volume manufacturing environments, job shops, and maintenance facilities where hole location accuracy is critical. The press fit installation method means no secondary locking hardware is needed, keeping fixture design compact and straightforward.

Key Features

• Type H press fit design installs permanently without a locking liner or lock screw
• Steel construction provides hardness and wear resistance suitable for repetitive drilling operations
• Inside diameter tolerance of +0.0001 to +0.0004 inches ensures close guidance of drill, reamer, or step drill
• Head outside diameter of 39/64 inches and head height of 7/32 inches provide positive seating against jig plate surface
• Non-counterbored head style for straightforward installation in standard jig plate bores
• Sold as a single unit, suitable for low-quantity fixture builds or replacement of worn bushings

Compatibility

Designed as an OEM-style replacement or new-installation component for drill jig fixtures requiring a Type H press fit headed bushing with a 0.209 inch inside diameter and 0.5 inch body outside diameter.

Installation Notes

Press fit bushings are installed by a toolmaker or machinist using an arbor press or hydraulic press; a hammer strike is not recommended as it can damage the head or distort the bore. The jig plate bore must be machined to the appropriate interference fit tolerance before installation. Once pressed in, the H3212GK is considered permanent and is not designed for field removal or replacement. Ensure all machine tools are de-energized and workpieces are secured before installing or servicing drill jig components.