Accupro 785069 ER40 Collet 0.875 Inch

Product Description

The ACCUPRO 785069 is an ER40 series collet designed for use in CNC machining centers, manual mills, and lathes equipped with ER40 collet chucks. It accepts a nominal shank diameter of 0.875 inches (7/8 inch) with a minimum collet capacity of 0.844 inches, providing a secure clamping range suitable for standard tooling shanks. The collet delivers concentric, repeatable tool holding for drilling, reaming, and milling operations. Machinists and CNC operators install this collet as a direct fit into any compatible ER40 chuck body. Its compact profile measures 2 inches in height and 1.75 inches across, keeping the overall assembly tight to the spindle.

This ER40 collet is suited for production and job-shop environments where accurate tool holding is required across a range of cutting tools. It fits standard ER40 collet chucks found on vertical machining centers, horizontal mills, and engine lathes. The 0.875 inch nominal size accommodates common end mill shanks, drill shanks, and reamer bodies within the listed capacity range. Sold individually, it can be added to an existing ER40 collet set or used as a standalone replacement when a worn or damaged collet needs swapping out.

Key Features

• ER40 collet series for use with ER40 chuck bodies
• Nominal collet size of 0.875 inches (7/8 inch) for standard tooling shanks
• Minimum collet capacity of 0.844 inches covers slight undersize shanks
• Compact dimensions: 2 inches height, 1.75 inches width and length
• Lightweight at 0.6 pounds for easy handling and reduced spindle load contribution
• Sold as a single unit with a minimum order quantity of 1

Compatibility

Designed as a direct-fit collet for ER40 series collet chucks used in standard CNC and manual machining applications requiring a 0.875 inch nominal collet size.

Installation Notes

Installation should be performed by a qualified machinist or CNC operator with the spindle powered down and the machine in a locked-out, tagged-out state per OSHA lockout/tagout procedures. Seat the collet fully into the ER40 chuck nut before threading onto the chuck body to avoid cross-threading or improper seating. Inspect the collet bore and chuck taper for chips or debris before assembly, as contamination will affect runout and clamping force. Use a calibrated ER40 collet wrench and torque the nut to the chuck manufacturer's specification found in the chuck documentation.