Accupro 775080 End Mill Holder CAT50 5/16 Inch Hole

Product Description

The ACCUPRO 775080 is a CAT50 taper shank end mill holder designed for precision milling operations on CNC machining centers. It accepts a 5/16-inch bore and delivers a 2.5-inch projection from gauge line to the nose face. The nose diameter measures 7/8 inch. This holder features through-coolant capability, supporting both through-spindle and DIN flange coolant delivery, making it suited for high-speed and high-efficiency material removal. With a TIR of 0.0002 inch and a balance rating of 25,000 RPM, it is built for demanding production environments where runout and vibration directly affect tool life and surface finish. A 1-8 drawbar thread secures the holder to the spindle. Machinists and CNC setup technicians install this holder as a direct interface between the machine spindle and end mill cutting tools.

This end mill holder is intended for use in CAT50-equipped vertical and horizontal machining centers in production shops, tool rooms, and job shops. It is appropriate for a range of end mill operations including slotting, profiling, and pocketing in both ferrous and non-ferrous materials. The through-coolant design is particularly valuable in deep cavity milling and applications where flood coolant does not reach the cutting zone effectively. The 2.5-inch projection provides clearance for workpiece features that require reach beyond a standard stub holder configuration.

Key Features

• CAT50 taper shank for direct mount to standard CAT50 machining center spindles
• 5/16-inch bore diameter accommodates standard end mill shank sizes
• 2.5-inch projection from gauge line for extended reach applications
• Through-coolant compatible via through-spindle and DIN flange coolant systems
• TIR of 0.0002 inch for tight runout tolerances at the tool tip
• Balanced to 25,000 RPM for high-speed machining stability
• 1-8 drawbar thread for secure spindle retention

Compatibility

Designed for use with CAT50 taper spindle machining centers equipped with through-spindle or DIN flange coolant systems and a 1-8 drawbar thread. Accepts end mills with a 5/16-inch straight shank.

Installation Notes

Installation should be performed by a qualified machinist or CNC setup technician. Power down and lock out the machining center before mounting or removing tool holders. Use the appropriate spanner wrench and follow the machine tool builder torque specifications for the drawbar. Inspect the taper bore and spindle taper for chips, nicks, or contamination before seating the holder to protect spindle accuracy and holder life.