Techniks 21003-60C Retention Knob CAT40 5/8-11 Thread

Product Description

The TECHNIKS 21003-60C is a CAT40 retention knob designed to secure toolholders in CNC machining center spindles. It features a 5/8-11 thread and a 60-degree angle radius that mates with the drawbar mechanism inside the spindle, ensuring positive clamping force during operation. The knob diameter measures 0.59 inches with an overall length of 2.25 inches. Through-coolant capability is included, making this knob compatible with coolant-through spindle setups. Licensed machinists and CNC service technicians install this hardware as part of toolholder maintenance or spindle rebuild work.

This retention knob is used in CNC vertical and horizontal machining centers equipped with CAT40 spindle tapers. It is a standard replacement component for facilities running production machining, tool and die work, or general metalworking operations. The 5/8-11 thread pitch is the industry-standard size for CAT40 toolholder applications. Through-coolant support makes it suited for high-pressure coolant delivery systems where coolant is routed directly through the spindle and toolholder.

Key Features

• CAT40 taper size for direct fitment in CAT40 spindle systems
• 5/8-11 thread for positive engagement with CAT40 toolholders
• 60-degree angle radius for proper drawbar seating and clamping
• Through-coolant capable for high-pressure coolant-through spindle setups
• 0.59-inch knob diameter and 2.25-inch overall length

Compatibility

Designed as an OEM-style replacement retention knob for CNC machining centers with CAT40 spindle tapers and 5/8-11 drawbar thread.

Installation Notes

Installation should be performed by a qualified CNC machinist or spindle technician. Power down and lock out the machine before removing or installing any spindle tooling components. Use a calibrated retention knob torque wrench to achieve proper installation torque - do not over-tighten by hand or with impact tools. Inspect the drawbar threads and toolholder threads for wear or contamination before reinstalling.