Boneham H4812LK Press Fit Headed Drill Bushing Steel

Product Description

The BONEHAM H4812LK is a Type H press fit headed drill bushing manufactured from hardened steel for use in jig and fixture applications. With a 0.5 inch inside diameter, a 0.75 inch body outside diameter, and a 0.75 inch length under head, this bushing provides precise drill guidance to maintain accurate hole location across repeated operations. The bore carries an inside diameter tolerance of +0.0001 to +0.0005 inches, ensuring consistent tool alignment. Hardness is rated at 60 to 65 HRC, delivering resistance to wear during high-cycle drilling. This is a permanent, non-renewable bushing installed by press fit into a prepared jig plate.

The H4812LK is suited for machine shops, toolrooms, and production environments where jig plates require a fixed, headed drill bushing. The headed design seats against the top face of the jig plate, preventing the bushing from being pushed through under drilling load. It is not counterbored. Typical installers include toolmakers, machinists, and fixture builders working to ANSI standards. This bushing fits standard jig plate applications where a 0.75 inch body OD press fit seat has been machined.

Key Features

• Type H headed design seats flush against jig plate face to resist axial push-through
• Inside diameter of 0.5 inches with tolerance of +0.0001 to +0.0005 inches for precise drill guidance
• Body outside diameter of 0.75 inches with 0.75 inch length under head
• Head outside diameter of 59/64 inches and head height of 7/32 inches
• Steel construction hardened to 60 to 65 HRC for extended wear life
• Press fit installation — permanent, non-renewable bushing

Compatibility

Designed as an OEM-style fixed drill bushing for jig plates and fixtures machined to accept a 0.75 inch body OD press fit bushing seat, per ANSI standards for headed drill bushings.

Installation Notes

Installation is performed by machinists or toolmakers using an arbor press to drive the bushing into a precision-bored hole in the jig plate. The receiving bore should be machined to the appropriate interference fit per ANSI drill bushing standards before installation. Once pressed in, this bushing is not designed for removal or replacement. Always confirm bore diameter and surface finish before pressing to avoid galling or cracking the jig plate.