Value Collection 231-4712 R8 Collet 3/16 Inch Steel

Product Description

The VALUE COLLECTION 231-4712 is a steel R8 collet designed for use in milling machines equipped with an R8 spindle taper. It accepts a 3/16 inch tooling shank and features a 7/16-20 drawbar thread for secure engagement with the machine spindle. With a total indicator runout (TIR) of 0.0007 inch, this collet holds cutting tools with the precision required for accurate milling operations. Machinists and tool-and-die professionals rely on R8 collets like this one to secure end mills, drill bits, and other shank tools in Bridgeport-style vertical mills and compatible knee mills.

This collet is suited for use in manual vertical milling machines with R8 spindle tapers, which are common in job shops, maintenance facilities, and machine tool training environments. The 3/16 inch bore size accommodates small-diameter tooling such as miniature end mills and engraving cutters. It is installed and removed using a drawbar wrench and is appropriate for both production and light-duty intermittent machining applications.

Key Features

• 3/16 inch bore diameter for small-shank tooling
• R8 taper profile for compatibility with R8 spindle machines
• 7/16-20 drawbar thread for positive spindle engagement
• 0.0007 inch TIR for precise tool holding and reduced runout
• Steel construction for durability under milling loads

Compatibility

Designed as an OEM-style replacement or supplemental collet for manual vertical milling machines equipped with an R8 spindle taper.

Installation Notes

R8 collets are installed and removed by a qualified machinist using a drawbar and drawbar wrench with the machine spindle powered off and the machine locked out. The spindle bore and collet taper should be clean and free of chips or oil before seating the collet. Do not overtighten the drawbar, as this can deform the collet bore and reduce accuracy over time.