Tool Holders

Basics

Each tool holder is made up essentially of 4 parts as outlined in the image at the bottom.

Retention Knob

Retention knobs are only used on tapered style tool holders, and are not applicable to HSK style and other modern interfaces. They screw into the end of the taper and are what the machine grabs on to when running. Many different styles exist.

Spindle Taper

The spindle taper is what interfaces with the spindle and the tool holder. It is extremely critical that this area be clean and free of pitting or corrosion as this will result in run out.

Tool Changer Interface

The tool changer interface is often unique to different machine manufacturers. This is the portion of the tool holder that allows the tool holder to be held in the tool carousel.

Cutting Tool Interface

The tool holder interface is what fastens the tool into the tool holder there are different methods for this but the main ones are as follows.

  • Conventional collet - ER, SYOZ (ORT), are some of the most common. This is by far the most common way to hold your tooling. Collets must be replaced after approx 500 hours of run time, unless it is subject to damage, then immediate replacement is recommended. when installing a tool into a collet at least 80% of the collet should be filled with the shank, whenever possible the entire collet should be covered.
  • Hydraulic - A more ridged and accurate option then a collet, the tool is placed in the unit and grease actually pressurizes around the shank. This provided less run out than a conventional collet, also under difficult conditions less vibration is present.
  • Shrink fit - Even more ridged and accurate than the hydraulic option, the tool holder is heated to allow it to expand, then the tool is placed into the holder and as the toolholder cools the tool is fastened into place. This provided an extremely ridged setup with very low run out. Disadvantage is that special equipment is required to make tool changes.
  • Monobody - A unique innovation offered by Royce//Ayr cutting tools. this system eliminates all forms of potential instability and run out that might occur between the cutting edge and the spindle taper.