Tooling & Workholding

Toolholders

The Toolholder is the essential connection between the machining center and the cutting tool. The toolholder fits into and is secured by the machining center’s spindle, and in turn secures the cutting tool such as a drill or end mill by clamping onto its shank. The taper of the toolholder matches the toolholder interface of the particular spindle. Toolholder tapers are often conical, including CAT and BT taper specifications. A different kind of taper, HSK, is not tapered at all, but instead includes a variety of flanges for securely locking the toolholder in place. Toolholders use different mechanisms for clamping the tool. A set screw can clamp onto a corresponding flat in the tool’s shank. Or, a collet can be compressed around the tool by tightening a nut that also surrounds the tool. More unusual clamping mechanisms include hydraulic toolholders, which compress a bladder of hydraulic fluid, as well as shrink fit toolholders, which clamp and release the tool by heating and cooling the toolholder’s metal to take advantage of thermal expansion and contraction. Other toolholder types use still other methods of clamping. Various clamping mechanisms aim to provide not just secure holding of the tool, but also tool concentricity to the centerline of the spindle that is accurate to a level of runout error appropriate to the tool and the machining process.

Machine Tool Database

Search and find specs for these machines.

Featured Zone Content

Gripper for machine tool

Video: Parts Gripper Allows Machine To Act As Its Own Robot


This footage shows a workpiece gripper that enables a machine to load and unload workpieces on its own.

toolholder balancing machine

Video: Balancing Tools And Toolholders


This video provides both the argument and methodology for performing offline balancing of tool/toolholder assemblies for high speed machining centers.



Tendo Platinum Precision Toolholders for Durability

By: Lori Beckman (editor)
Schunk’s Tendo Platinum toolholder offers durablity, user friendliness and precision for almost any milling, drilling and reaming application.

Keyless Drill Chucks Ensure Precise Hole Sizing

By: Edited by Jedd Cole
Albrecht’s precision drill chucks, available from Royal Products, are designed to ensure precise hole sizing and extend drill life.

NT Tool PHC-S

Hydraulic Chuck Toolholder Can Replace Shrink-Fit Holders

By: Edited by Jedd Cole
NT Tool offers its high-accuracy hydraulic chucks in a slim PHC-S toolholder for use in tight spaces.

Steadyline Turning Bars Reduce Vibration

By: Lori Beckman (editor)
Seco Tools LLC is adding turning bars to this Steadyline line of damped tooling.

A system for turning oil-industry face grooves on a machining center uses an adjustable toolholder along with an NC code generator for creating the unusual path.

Video: Machining API Groove with “Spirograph” Tool Path

By: Peter Zelinski
A system for turning oil-industry face grooves on a machining center uses an adjustable toolholder along with an NC code generator for creating the unusual path.


MMS ONLINE
Channel Partners
  • Techspex