Accupro 12633404705 Boring Head MT3 7/8-20 Threaded

Product Description

The ACCUPRO 12633404705 is a taper shank boring head adapter designed to connect a boring head to a machine spindle using a Morse Taper 3 (MT3) shank and a 7/8-20 threaded mount interface. This adapter serves as the connection point between the boring head body and the machine tool, transmitting rotational force during precision boring operations. It is used in manual milling machines, drill presses, and similar machine tools where MT3 spindle tooling is standard. Installation and removal are handled by machinists and machine tool operators. The part does not support coolant-through capability.

This adapter is suited for job shops, toolrooms, and production environments running MT3-compatible machines. Typical applications include bore sizing, bore finishing, and precision hole enlargement in ferrous and non-ferrous workpieces. The 7/8-20 threaded interface accepts a compatible boring head body. This part ships as a single unit and is intended as either a replacement adapter or a new setup component for an existing boring head assembly.

Key Features

• MT3 taper shank for direct fit into MT3-spindle machines without an additional adapter
• 7/8-20 threaded mount provides secure, positive connection to compatible boring head bodies
• No coolant-through passage — suited for dry or flood-coolant-from-outside setups
• Compact weight of 1.8 pounds reduces spindle load during boring operations
• Single-piece construction minimizes runout contributors at the shank-to-head interface

Compatibility

Designed for use with boring head bodies that accept a 7/8-20 threaded shank connection, mounted in machine tool spindles with a Morse Taper 3 (MT3) taper. Verify spindle taper size and boring head thread specification before ordering.

Installation Notes

Installation is performed by a qualified machinist or machine tool operator. Power down and lock out the machine spindle before installing or removing the taper shank adapter. Clean both the MT3 spindle bore and the taper shank with a lint-free cloth to remove chips, oil film, and debris before seating — any contamination will affect runout. Thread the boring head body onto the 7/8-20 mount and secure per the boring head manufacturer's torque guidance; do not use impact tools on the threaded interface.