Parlec 4015TRK Retention Knob CAT40 5/8-11 Thread

Product Description

The PARLEC 4015TRK is a CAT40 retention knob designed to secure tool holders in CNC machining center spindles that use the CAT40 taper standard. It threads into the drawbar mechanism at 5/8-11 UNC and pulls the tool holder firmly into the spindle taper during operation. The knob features a 60-degree angle radius, a 0.589-inch knob diameter, and an overall length of 2.31 inches. Style C geometry keeps it compatible with standard CAT40 drawbar configurations. This component is installed by CNC machine operators and toolroom machinists as part of routine tool holder setup and maintenance.

The 4015TRK fits CAT40 tool holders used in vertical and horizontal machining centers. It is a direct-thread retention knob suited for production environments where consistent clamping force and repeatable tool holder seating are required. The 0.635-inch pilot diameter and 0.391-inch neck diameter are dimensioned to CAT40 specifications, and the 0.13-inch flange thickness and 1.268-inch knob-to-flange length ensure proper drawbar engagement depth across standard CAT40 spindle designs.

Key Features

• CAT40 taper size for compatibility with standard CAT40 machining center spindles
• 5/8-11 UNC thread engages directly with the spindle drawbar
• 60-degree angle radius for proper seating against the drawbar pull stud contact surface
• 0.589-inch knob diameter and 0.635-inch pilot diameter machined to CAT40 dimensional standards
• Style C configuration suits common CAT40 drawbar systems
• No through-coolant bore keeps the design simple for standard dry or flood-coolant applications

Compatibility

Designed as an OEM-style retention knob for CAT40 tool holders used in machining centers with a 5/8-11 drawbar thread and CAT40 spindle taper.

Installation Notes

Retention knobs are installed and removed by toolroom machinists or CNC setup personnel using a retention knob wrench sized for the 5/8-11 thread. Always power down and lock out the machine spindle before servicing tool holders or replacing retention knobs. Do not overtighten the retention knob, as excessive torque can distort the tool holder taper and affect runout. Inspect the knob and drawbar threads for wear or damage at each tool change interval.