Accupro 587479 ER20 Collet 0.314 Inch 8.00mm

Product Description

The ACCUPRO 587479 is an ER20 series collet designed for use in CNC machining, milling, and drilling applications. It accepts shank diameters up to 0.314 inches (8.00mm) with a minimum collet capacity of 0.275 inches (7.0mm), giving machinists a defined clamping range for secure toolholding. The collet achieves a total indicator runout (TIR) of 0.01mm, supporting precision work where concentricity and repeatability are critical. This type of collet is a standard consumable in machine shops and tool rooms, installed by machinists and CNC operators as part of routine tooling setup.

ER20 collets are widely used in collet chucks mounted to CNC machining centers, manual mills, and drilling machines. The ER20 series is one of the most common collet standards in production and job-shop environments. This collet is suited for both ferrous and non-ferrous material cutting operations where consistent tool clamping and low runout are required. It is sold individually and is compatible with any ER20-standard collet chuck.

Key Features

• ER20 collet series for use with ER20-standard collet chucks
• Clamping range of 0.275 inches (7.0mm) minimum to 0.314 inches (8.00mm) maximum
• 0.01mm TIR for high concentricity and repeatable tool positioning
• Sold individually, compatible with standard ER20 collet chuck systems
• Suitable for milling, drilling, and reaming applications

Compatibility

Designed as a direct-fit replacement or spare for any ER20-standard collet chuck system used in CNC and manual machining equipment.

Installation Notes

Installation is performed by machinists or CNC operators. Before inserting or removing a collet, ensure the spindle is fully stopped and the machine is powered down or in a safe locked-out state. The collet should be seated fully into the collet nut before threading onto the chuck body. Do not exceed the rated clamping range for this collet series, as over- or under-sized shanks can reduce clamping force and increase runout.