Accupro 771158 CAT50 End Mill Holder 1 in Hole Through Coolant

Product Description

The ACCUPRO 771158 is a CAT50 dual contact taper shank end mill holder designed for use in CNC machining centers requiring high-speed, high-precision tool holding. It accepts a 1-inch bore and provides 8 inches of projection from the spindle face, giving clearance for deep-reach milling applications. The dual contact taper interface engages both the taper and the spindle face simultaneously, improving rigidity and reducing runout. Total indicator runout (TIR) is rated at 0.0002 inches, and the holder is balanced to 25,000 RPM. Through-coolant capability is supported via through-spindle and DIN flange coolant delivery. A licensed machinist or CNC setup technician is the typical installer.

This holder suits vertical and horizontal machining centers equipped with CAT50 spindles. The 8-inch projection makes it appropriate for deep-cavity work, long-reach end milling, and applications where standard-length holders cannot provide adequate clearance. The 2-23/64-inch nose diameter accommodates standard end mill collet and direct-mount configurations. With a clamping depth of 2.36 inches and a retention knob thread size of 1-8, it fits standard CAT50 drawbar systems commonly found in production and job-shop environments.

Key Features

• CAT50 dual contact taper shank for enhanced spindle rigidity and face contact
• 1-inch bore with 8-inch projection for extended reach milling operations
• TIR of 0.0002 inches for precision tool positioning
• Balanced to 25,000 RPM for high-speed machining compatibility
• Through-coolant support via through-spindle and DIN flange delivery
• Retention knob thread size of 1-8 fits standard CAT50 drawbar systems

Compatibility

Designed as an OEM-style replacement and direct-fit toolholder for CAT50-spindle CNC machining centers requiring dual contact taper interface and 1-inch bore end mill holding.

Installation Notes

Installation should be performed by a qualified machinist or CNC toolroom technician. Always power down and lock out the machining center spindle before installing or removing toolholders. Ensure the spindle taper and holder taper are clean and free of chips, oil film, and burrs before seating. Torque the retention knob to the machine manufacturer's specified value using a calibrated torque wrench — do not exceed the drawbar's rated clamping force.