Accupro 775350 End Mill Holder R8 Taper 5/8 Inch

Product Description

The ACCUPRO 775350 is an R8 taper shank end mill holder designed for use in milling machines equipped with an R8 spindle interface. It accepts end mills with a 5/8 inch shank diameter and provides a 1.1 inch projection from the spindle face, giving the cutter the clearance needed for typical milling operations. The holder achieves a total indicator runout (TIR) of 0.0002 inch, supporting accurate, repeatable cutting performance. Drawbar thread size is 7/16-20, which is standard for R8 tooling. This holder is installed by machinists and tool room technicians setting up vertical milling machines for production or maintenance work.

This end mill holder is suited for vertical knee mills, Bridgeport-style machines, and other milling equipment built around the R8 spindle standard. It is appropriate for general machining environments including job shops, maintenance facilities, and production floors where R8 tooling is the shop standard. The 5/8 inch bore accommodates a wide range of two- and four-flute end mills in that shank size. Through-coolant is not supported by this holder.

Key Features

• R8 taper shank for direct fit in R8-spindle milling machines
• 5/8 inch bore diameter accepts standard 5/8 inch shank end mills
• 1.1 inch projection from spindle face for clearance in typical setups
• TIR of 0.0002 inch for precise, low-runout tool holding
• 7/16-20 drawbar thread matches standard R8 machine drawbars
• No through-coolant, suitable for dry or flood coolant external application

Compatibility

Designed as an OEM-style replacement and standard tooling option for milling machines equipped with an R8 spindle taper and a 7/16-20 drawbar thread.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician. Before installing or removing the holder, power down the milling machine and confirm the spindle is fully stopped. Insert the R8 taper fully into the spindle bore, then tighten the drawbar to secure the holder — do not use the drawbar to pull the taper into the spindle under power. Inspect the taper bore and the holder shank for chips or burrs before each use to maintain low runout.