The Value of Double-Checking Your Programs
Using simulation software to validate CNC programs for large, expensive precision parts helped one manufacturer reach a delicate balance of speed and accuracy.
“If you have a $20,000 part and you scrap it out, you can pretty much buy the software with that one scrapped part,” says Shawn Eisenschenk, manufacturing engineer for Kurt Manufacturing. The software he is referring to is NCSimul Machine simulation software from Spring Technologies. Kurt Manufacturing began using this software to ensure that short runs of its high-value parts were efficient.
Previously, the company had been using a simulation program included with its CAM package to validate that its programs appeared free of errors, and once the program was validated, a postprocessor would translate it into G code. However, the CAM system’s pre-G-code simulation did not always accurately show the positioning and movement of the actual machine and tools in use. If the G code generated unexpected machine motion or other errors, the program might not be apparent until the machine ran the part, even though the program appeared to be error-free in the CAM simulation.
The simulation software provides machining verification in three steps. First, it investigates and corrects coding errors. Then it simulates to locate collisions and correct motion errors. Finally, it validates the part cut and machining result. “Through NCSimul, we get exactly what the machine is seeing or reading,” Mr. Eisenschenk says.
Kurt does not use NCSimul’s cycle-time optimization feature on its short runs, but the shop has found that it works well for some of its other jobs. Learn more in in this full-length case history.
The ability to import complex curves into CNCs promises to let shops finally get beyond old limitations imposed by contouring with linear interpolation. Faster and smoother cutting will be the result.
Watch this short video from Sandvik Coromant to learn about the advantages of thread milling.
Finally there is an alternative to ballnose endmills for finishing 3D parts. The combination of finishing tools shaped to provide more cutting surface and a CAM system with the ability to apply them on a five-axis machining center can dramatically reduce finishing cycle times while delivering better surface finishes.