Collis Tool 68205 End Mill Holder CAT40 1/2 Inch Bore

Product Description

The COLLIS TOOL 68205 is a CAT40 taper shank end mill holder designed for securing end mills in CNC machining centers and milling machines. It accepts a 1/2 inch bore diameter and delivers a 1.375 inch projection from the spindle face to the tool nose, keeping the cutter close to the spindle for improved rigidity. The 1.75 inch nose diameter provides a robust clamping surface. With a total indicator runout (TIR) of 0.0002 inch, this holder maintains the close tolerances required for precision milling operations. A 5/8-11 drawbar thread engages the machine spindle, and the holder is balanced to 20,000 RPM for compatibility with high-speed machining applications. Machining professionals and tool crib managers rely on this holder for consistent, repeatable tool positioning.

This holder is suited for use in production and job-shop environments running CAT40-spindle vertical or horizontal machining centers. It is appropriate for light to medium milling work where a 1/2 inch shank end mill is the cutting tool of choice. The CAT40 taper is one of the most common spindle interfaces in North American CNC shops, making this holder a versatile addition to any tooling inventory. It does not feature through-coolant capability, so it is best applied in operations using flood or mist coolant delivered externally.

Key Features

• CAT40 taper shank for compatibility with standard CAT40 CNC machining center spindles
• 1/2 inch bore diameter accepts standard 1/2 inch shank end mills
• 1.375 inch projection minimizes overhang and supports rigidity during cutting
• TIR of 0.0002 inch supports precision and surface finish requirements
• Balanced to 20,000 RPM for high-speed machining center use
• 5/8-11 drawbar thread for secure spindle engagement

Compatibility

Designed as a direct-fit toolholder for CAT40-spindle CNC milling machines and machining centers using 1/2 inch shank end mills. No through-coolant port is present on this holder.

Installation Notes

Installation should be performed by a qualified machinist or tooling technician following the machine builder's drawbar torque and toolchange procedures. Power down and lock out the machining center before loading or unloading the holder from the spindle. Use a proper spanner wrench or end mill holder wrench to tighten the clamping nut to the tool shank - do not use improvised tools that could damage the bore or nut. Verify runout at the tool tip with a dial indicator after installation before beginning any cut.