Accupro 88.113.50.AP Retention Knob CAT50 1-8 Thread

Product Description

The ACCUPRO 88.113.50.AP is a CAT50 retention knob engineered for use in CNC machining centers that use the CAT50 taper toolholder standard. It features a 1-8 inch thread, a knob diameter of 0.9055 inches, and an overall length of 3.3524 inches. The through-coolant design includes a coolant hole diameter of 0.1969 inches, allowing coolant to pass directly through the toolholder assembly to the cutting zone. High-torque construction provides secure clamping force under demanding cutting conditions. This knob is installed by machinists and toolroom technicians during toolholder assembly or replacement.

This retention knob is suited for CAT50 toolholder assemblies used in heavy-duty vertical and horizontal machining centers. The Style B configuration, 90-degree angle radius, and precise dimensional tolerances make it a reliable choice for production environments where toolholder pullout or vibration are concerns. Knob-to-flange length measures 1.7775 inches and flange thickness is 1.3839 inches, with a neck diameter of 0.6693 inches. Typical applications include production milling, boring, and drilling operations on machines equipped with CAT50 spindles.

Key Features

• CAT50 taper size for compatibility with CAT50 spindle toolholder systems
• 1-8 inch thread for secure engagement with the drawbar mechanism
• Through-coolant capable with a 0.1969 inch coolant hole diameter
• High-torque construction for reliable clamping under heavy cutting loads
• Style B design with 90-degree angle radius for precise seating
• Compact 0.6693 inch neck diameter reduces interference in tight toolholder configurations

Compatibility

Designed as a replacement or spare retention knob for CAT50 taper toolholder assemblies used in CNC machining centers equipped with CAT50 spindles and 1-8 drawbar threads.

Installation Notes

Retention knobs are installed by qualified machinists or toolroom technicians. Before replacing a retention knob, ensure the machine spindle is fully de-energized and the drawbar mechanism is disengaged. Use the appropriate spanner or retention knob installation tool to achieve proper torque without damaging the thread engagement. Do not install a retention knob without verifying that the thread specification of the knob matches the drawbar of the host machine.