Boring bar

In woodworking, the boring tool is static in size and used to form circular plunge cuts.

In metal boring the tool can be plunged and dragged on the X or Y axes to create a slot or asymmetrical hole or channel, or it may be moved only in an up-and-down motion (on the Z axis) to create a perfect circular hole.

The lower part (bar holder) is connected via dovetail, T-slots or a smooth notch with an adjustment for bore diameter via the dial screw.

The shorter the distance between the tool holder and the material, the less distortion created from vibration or unbalanced gyroscopic effects.

Use of a boring head increases the mass of the tool holder and decreases the distance.

A part's-eye view of a boring bar. It enters into an existing hole (drilled or cored), and the single-point cutters cut a cylindrical toolpath that is extremely accurate, being defined by the spindle's rotation and the linear motion of the Z-axis slide. In this case, the tool bits are of the brazed carbide type.
Boring bar marked B