Accupro 778986 Boring Head CAT40 Threaded Mount

Product Description

The ACCUPRO 778986 is a taper shank boring head designed for precision boring operations on CNC machining centers. It features a CAT40 taper shank with a 7/8-20 threaded mount, providing a rigid, repeatable connection to the spindle. The projection measures 1.75 inches, positioning the boring head at the correct working distance from the spindle face. This toolholder is installed by machinists and CNC operators in production and job-shop environments where accurate bore sizing is required. The threaded mount design allows secure attachment of a boring head body, supporting fine diameter adjustments during setup.

This boring head shank is suited for use on vertical and horizontal machining centers equipped with CAT40 spindle tapers. It is appropriate for both roughing and finish boring passes in ferrous and non-ferrous materials. Typical applications include enlarging, finishing, and truing bored holes to close tolerances in workholding fixtures, housings, and mechanical components. The 1.75-inch projection provides clearance for standard boring head configurations in typical VMC and HMC setups.

Key Features

• CAT40 taper shank for use with CAT40-equipped machining centers
• 7/8-20 threaded mount for secure boring head attachment
• 1.75-inch projection for standard boring head reach
• No coolant-through design - suited for external coolant delivery setups
• Compact 2 x 2 inch cross-section for reduced interference in tight setups

Compatibility

Designed as an OEM-style replacement or new-installation taper shank for machining centers with CAT40 spindle interfaces and boring heads with a 7/8-20 threaded mount connection.

Installation Notes

Installation should be performed by a qualified machinist or CNC setup technician. Ensure the spindle is fully powered down and locked out before mounting or removing the taper shank. Clean the CAT40 taper and spindle bore thoroughly before seating to prevent fretting and runout. Torque the drawbar to the machining center manufacturer's specification and verify runout with a dial indicator before committing to a boring pass.