Accupro 775522 Shell Mill Holder NMTB50 Taper Shank

Product Description

The ACCUPRO 775522 is a shell mill holder with an NMTB50 taper shank designed for horizontal and vertical milling machines equipped with a through-spindle coolant system. It accepts shell mills in the 4 to 5 inch cutting diameter range and features a 1-1/2 inch pilot diameter for secure cutter seating. The flange-to-nose projection measures 1.88 inches, providing the clearance needed for most standard shell mill bodies. Total Indicator Runout (TIR) is rated at 0.0002 inches, supporting accurate, low-vibration cuts across a wide range of ferrous and non-ferrous materials. Machinists and toolroom technicians install this holder in production milling centers, knee mills, and horizontal machining centers.

This holder is suited for production and job-shop environments where coolant-through tooling is required to extend tool life and manage chip evacuation at the cutter face. The through-spindle coolant delivery directs fluid directly to the cutting zone, reducing heat buildup during face milling, shoulder milling, and slotting operations. The 3/4-16 lock screw thread secures the shell mill body to the holder. It is compatible with NMTB50 spindle tapers commonly found in knee mills and vertical machining centers operating in that taper standard.

Key Features

• NMTB50 taper shank for positive spindle engagement on compatible machines
• Through-spindle coolant delivery directs fluid to the cutting zone
• 1-1/2 inch pilot diameter for accurate shell mill positioning
• 0.0002 inch TIR for low runout and consistent surface finish
• 1.88 inch flange-to-nose projection for standard shell mill body clearance
• 3/4-16 lock screw thread for secure cutter retention

Compatibility

Designed for use with shell mills in the 4 to 5 inch cutting diameter range on machines equipped with an NMTB50 spindle taper and through-spindle coolant capability.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician. Power down and lock out the machine spindle before mounting or removing the holder. Inspect the spindle taper and holder taper for nicks, burrs, or contamination before seating — even minor debris will affect TIR and cutter runout. Torque the draw bar and lock screw according to the machine tool manufacturer specifications; do not substitute generic values.