Accupro 778906 NMTB40 to JT33 Taper Adapter

Product Description

The ACCUPRO 778906 is an NMTB to Jacobs Taper adapter designed to connect a Jacobs Taper 33 drill chuck to an NMTB40 spindle on a milling machine or drill press. It features an NMTB40 outside taper for direct mounting to compatible machine spindles and a JT33 inside taper to accept standard Jacobs Taper 33 drill chucks. With a projection of 0.65 inches, this adapter keeps the chuck positioned close to the spindle for reduced runout and improved rigidity. The coolant-through feature is not supported. This adapter is used by machinists and tool room technicians working with NMTB40-spindle equipment.

This adapter is suited for machine shop environments where a Jacobs Taper 33 chuck must be mounted on an NMTB40 spindle. Typical applications include drilling operations on knee mills, bed mills, and vertical machining centers equipped with NMTB40 tooling. The short 0.65-inch projection minimizes overhang, which helps maintain accuracy during drilling and reaming operations. It is a direct-fit, solid adapter with no moving parts, making it a straightforward solution for converting spindle interfaces.

Key Features

• NMTB40 outside taper for direct mounting to NMTB40 machine spindles
• JT33 inside taper accepts standard Jacobs Taper 33 drill chucks
• 0.65-inch projection keeps chuck close to spindle for improved rigidity
• No coolant-through design — solid adapter construction
• Single-piece adapter with no adjustable components

Compatibility

Designed as an OEM-style replacement or direct-fit adapter for NMTB40-spindle milling machines and drill presses requiring a JT33 Jacobs Taper chuck interface.

Installation Notes

Installation is performed by a qualified machinist or tool room technician. Power down and lock out the machine spindle before installing or removing any tooling adapter. Ensure the NMTB40 taper and the JT33 socket are clean and free of chips, oil, or debris before seating the adapter. Follow the machine manufacturer's draw bar torque guidelines when securing the adapter in the spindle.