Parlec 5UMER20-0250 ER20 Collet 1/4 Inch

Product Description

The PARLEC 5UMER20-0250 is an ER20 series collet designed for precision tool holding in CNC machining centers, milling machines, and other rotating spindle applications. It accepts a 0.25 inch (1/4 inch) shank diameter with a minimum collet capacity of 0.211 inches, offering a clamping range suited to close-tolerance tooling. The overall length is 1.24 inches and the overall diameter is 0.827 inches. Total indicator runout (TIR) is rated at 0.0002 inches, making this collet appropriate for finishing operations and applications where concentricity directly affects surface finish and tool life. Machinists and CNC operators install this collet into a compatible ER20 collet chuck or toolholder.

The PARLEC 5UMER20-0250 is used in precision machining environments where repeatable tool runout and secure clamping are required. Typical applications include end milling, drilling, reaming, and tapping on both vertical and horizontal machining centers. The ER20 collet series is widely adopted in production and job-shop settings where a broad range of shank diameters must be accommodated within a single toolholder system. This collet is suited for shops holding tolerances in the tenths and requiring consistent tool change repeatability across multiple setups.

Key Features

• ER20 collet series with 0.25 inch (1/4 inch) nominal shank capacity
• 0.0002 inch TIR rating supports finishing and close-tolerance operations
• Minimum collet capacity of 0.211 inches provides a functional clamping range
• Overall length of 1.24 inches for compact toolholder integration
• Overall diameter of 0.827 inches consistent with ER20 collet chuck bore specifications
• Lightweight at 0.19 pounds, suitable for high-speed spindle applications

Compatibility

Designed for use in ER20-standard collet chucks and toolholders that accept the ER20 collet series with a 0.25 inch bore capacity.

Installation Notes

Installation is performed by qualified machinists or CNC setup technicians. The spindle must be stopped and the machine placed in an appropriate lock or safe state before inserting or removing collets. Seat the collet fully into the ER20 collet chuck nut before threading onto the toolholder body to prevent damage to the collet taper. Verify TIR with a dial indicator after torquing the collet nut to confirm concentricity meets job requirements.