CAM industry leader DP Technology put the latest version of its ESPRIT software, 2008, to the test when it performed a successful test cut utilizing an innovative new machining cycle that simultaneously utilizes a B-axis while performing a traditional contour turning operation with a standard lathe insert.

This innovative new lathe machining cycle cuts inner and outer profiles in one step with just one tool that would have normally required a series of turning tools with differing tool geometry.

B-axis contouring is a finishing operation that continuously rotates the B-axis while turning contours allowing the cutting tool to reach areas that would otherwise be inaccessible due to the tool’s geometry. Utilizing this new machining cycle reduces the number of cutting tools required, the number of tool changes, and results in a smooth and stepless surface and, ultimately, a significant savings in both time and money.

Olivier Thenoz, DP Mill-turn product manager, performed the test cut at the Los Angeles office of the Mori Seiki machine tool company in cooperation with Randy Felten, manager, applications, for Mori Seiki. The pair performed the cut, a B-axis contouring lathe operation, on a Mori Seiki NT3150 DCG. The result was a part produced with a final finishing cut that followed the entire inner and outer profile with a single tool rotating smoothly about the B-axis, demonstrating the varied capabilities of the new operation.

“If you’re using one tool instead of three, you could be saving as much as 20 seconds,” said Thenoz. “If you multiply that by the number of parts you’re producing, the results can be very interesting.” Thenoz added that, while ESPRIT 2008 offers comprehensive improvements for all users, the addition of the B-axis contouring capability is a unique opportunity for advanced users, or for those who seek to streamline operations.

“The axis control is amazing,” Felten said of the B-axis contouring, following the test cut. “I’ve never seen this before, though the possibility has been discussed. There are people who have wanted to do this, but there was no one who did.”

More About B-Axis Contouring
The B-axis contouring cycle is based on the SolidTurn contouring cycle, as most of the technology settings are common to both operations. The tool orientation defined on the strategy page defines the B-axis angle, and this orientation is used during the lead-in move. During the cut, the tool orientation changes based upon the B-axis strategy. The lead-out move uses the final tool orientation angle.

Two strategies used to control the B-axis angle variation are the minimization of the change of lead angle and the minimization of the change of orientation angle. Minimum and maximum lead angles define the allowable range of the local lead angle of the tool. The local lead angle is measured from an imaginary line perpendicular to the front edge of the tool.

Because the B-axis orientation angle is relative to the vertical axis and also takes into account the tool holder orientation, the tool angle will never pass minimum and maximum B-angle limits. When collision detection is enabled, it prevents collisions between the part and the tool. The collision detection works from the tool geometry and clearances input by the user.