Value Collection 231-4811 R8 Round Collet 11mm

Product Description

The VALUE COLLECTION 231-4811 is a steel R8 round collet designed for milling machines equipped with an R8 spindle taper. It accepts an 11mm tool shank and features a 7/16-20 drawbar thread for secure clamping. The collet holds a total indicator runout (TIR) of 0.0007 inches, supporting accurate tool positioning during cutting operations. Machinists and tool-and-die professionals use this collet as a standard workholding component when mounting end mills, drill bits, and similar round-shank tooling in Bridgeport-style and compatible vertical knee mills.

This R8 collet is suited for job shop, maintenance, and production milling applications where an 11mm collet size is required. It fits manual vertical milling machines with an R8 spindle, which remain common in small shops, vocational training environments, and field maintenance facilities. The steel construction provides durability through repeated tightening and release cycles.

Key Features

• 11mm collet bore accepts standard 11mm round-shank tooling
• R8 taper profile fits R8 spindle machines
• 7/16-20 drawbar thread for positive clamping
• 0.0007 inch TIR for consistent tool concentricity
• Steel construction for durability under repeated use

Compatibility

Designed as an OEM-style replacement or standard collet for manual vertical milling machines with an R8 spindle taper and a 7/16-20 drawbar thread.

Installation Notes

Installation is performed by machinists or qualified machine operators. Power down and de-energize the milling machine and lock the spindle before inserting or removing the collet. Insert the collet into the spindle taper, engage the drawbar thread by hand, and tighten the drawbar with the appropriate wrench — do not overtighten. Inspect the collet bore and spindle taper for chips or damage before each use to maintain runout performance.