We know about the basic XYZ axes on a machine, but what about another axis called a B axis? What is it, and what are its advantages? Using past Production Machining and Modern Machine Shop articles, I researched the B axis in order to share some basic information with you regarding the additional cutting capability of this articulating tool axis.
The B axis is capable of moving in an arbitrary five-axis plane rather than being restricted to the traditional live tool motions found on a Swiss machine, where a milling cutter can be positioned axially or radially to either the diameter or the face of the part.
However, the B axis name is not always given to the same machine motion on all turn-mill machines. Sometimes the B axis is the rotation of the milling head. This orientation enables the milling head to work on the side or end of a workpiece gripped in either spindle from any angle. On other turn-mill machines, though, the linear motion that enables a second spindle or subspindle to approach the main spindle for a workpiece pick-off is referred to as a B axis.
Use of a machine with the contouring B axis capability is best suited for complex geometry parts in lower volumes. Complex parts can be machined in one setup by using the B axis cutting capability, which helps avoid the need to spend a lot of time reconfiguring the tool zone to accommodate a different part or particular machined feature. This is especially useful in the medical industry, where sculpted, low-volume parts are often machined. Medical shops can also benefit from the ability to seamlessly incorporate attachments for thread whirling, broaching and other specialty operations into the B-axis tool post.
The ability to manipulate the tool to any angle in very precise increments is a primary benefit of having a B axis. With a programmable B axis, it’s just a matter of programming that angle. Using traditional methods, this can be a slow and tedious process.
For more detailed information about the B axis, visit “The Buzz about the B Axis” and “Swiss-Type Sculpting Serves Complex Parts Complete.” To learn about the B axis on a gang tool-based Swiss machine, read “Optimizing B Axis on Gang Tool-Based Swiss Machines.”