Parlec 50TRK Retention Knob CAT50 1-8 Thread Style a

Product Description

The PARLEC 50TRK is a CAT50 retention knob designed to secure toolholders in CAT50 spindle interfaces on CNC machining centers. Machined to precise tolerances, this Style A knob features a 1-8 UNC thread, a 45-degree angle radius, and a 1.14-inch knob diameter. Through-coolant capability is built in via a 0.468-inch coolant hole, allowing pressurized coolant delivery directly through the spindle. At 2.54 inches overall length and 0.5 pounds, it provides the clamping interface between the drawbar and the toolholder body. Installation requires no special tooling beyond a torque wrench and proper drawbar engagement.

This retention knob is used in CAT50 toolholder assemblies installed in horizontal and vertical machining centers equipped with CAT50 spindles. It is the standard hardware component that machining technicians, tool crib personnel, and CNC setup techs install when assembling or replacing toolholder pull studs. Through-coolant-capable spindle setups benefit from the integrated 0.468-inch coolant passage, which maintains flow continuity from the machine spindle through the toolholder to the cutting tool.

Key Features

• CAT50 taper size for direct engagement with CAT50 spindle drawbars
• 1-8 UNC thread for positive drawbar clamping
• 45-degree angle radius, Style A configuration
• Through-coolant capable with 0.468-inch coolant hole diameter
• 1.14-inch knob diameter with 0.82-inch neck diameter for clearance fit
• 1.026-inch pilot diameter for accurate toolholder seating

Compatibility

Designed as an OEM-style retention knob for CAT50 toolholders requiring a 1-8 UNC thread pull stud with Style A geometry and through-coolant capability.

Installation Notes

Installation is performed by qualified machining technicians or tool crib personnel during toolholder assembly. The spindle must be fully powered down and the machine placed in a safe state before handling toolholder components. Apply the manufacturer-recommended drawbar torque specification for the machine spindle - do not over-torque, as this can damage the toolholder taper or thread engagement. Inspect the coolant passage for obstructions before assembly when through-coolant delivery is required.