Parlec 4030TRK Retention Knob CAT40 5/8-11 Thread

Product Description

The PARLEC 4030TRK is a CAT40 retention knob designed to secure toolholders in CAT40 spindle tapers on CNC machining centers. It features a 5/8-11 thread and a 75-degree angle radius that seats firmly against the drawbar, maintaining consistent pull-force and toolholder registration. The knob diameter measures 0.747 inches with a 0.55-inch neck diameter and a 0.635-inch pilot diameter. A through-coolant passage with a 0.281-inch coolant hole diameter allows directed coolant flow directly through the spindle and toolholder assembly. Overall length is 2.06 inches. The 4030TRK is installed by CNC machinists and toolroom technicians as a standard consumable component in CAT40 toolholder setups.

The 4030TRK is suited for CAT40 toolholders used in vertical and horizontal machining centers operating with through-spindle coolant systems. The Style D designation indicates a specific knob geometry compatible with common CAT40 drawbar configurations. Knob-to-flange length is 1.02 inches and flange thickness is 0.18 inches, dimensions that affect seating depth and drawbar engagement. This knob is appropriate for production and job-shop environments where CAT40 tooling is standard.

Key Features

• CAT40 taper size for direct compatibility with CAT40 spindle drawbar systems
• 5/8-11 thread engages standard CAT40 drawbar threads
• 75-degree angle radius for consistent drawbar pull-force and seating
• Through-coolant capable with 0.281-inch coolant hole diameter
• Style D knob geometry for proper drawbar engagement
• Compact 2.06-inch OAL fits standard CAT40 toolholder retention pocket

Compatibility

Designed as an OEM-style retention knob for CAT40 toolholders used with CAT40 spindle drawbar systems on CNC machining centers.

Installation Notes

Retention knobs should be installed and torqued by a qualified machinist or toolroom technician using an appropriate retention knob torque wrench. Always power down and lock out the machining center spindle before removing or installing retention knobs. Do not over-tighten, as excess torque can distort the toolholder taper and degrade runout. Inspect the knob threads and drawbar threads for wear or damage before each installation.