What Is a Milling Machine Chuck?
A milling machine chuck is a specialized tool holder designed for securing various cutting tools, such as end mills and drills, to the spindle of machining centers or milling machines. These chucks come in different types, tailored for specific applications, ranging from heavy-duty to light-duty cutting, and are selected based on the machining center’s design and the machining task at hand.
Some milling machine chucks feature two or three-sided contact surface restraints to minimize displacement caused by high-speed spindle rotation, enhancing precision during operations.
Uses of Milling Machine Chucks
Certain milling machine chucks are equipped with advanced mechanisms like a spindle type that amplifies rotation speed and a center-through design that allows the delivery of cutting fluid directly to the cutting tools through the chuck. The part of the chuck that connects to the machine, known as the shank, varies in type. NT shanks are common in general-purpose milling machines, whereas BT shanks or HSK standard shanks are used in NC machines and machining centers.
Principle of Milling Machine Chucks
Milling machine chuck shanks are categorized by size: No. 30, No. 40, and No. 50. The BT shank, predominantly used in machining centers, is the most common type both in Japan and internationally. The HSK shank, also primarily for machining centers, differs from the BT shank in its shorter length and the absence of a pull bolt. The NT shank, similar to the BT shank but lacking a flange for automatic tool change (ATC) functionality, is typically used in machines without ATC, such as general-purpose milling machines.