Closed-loop Adaptive Machining using NX CAM

Aerospace manufacturers face an unforgiving challenge: complex components like turbine airfoils demand extremely tight dimensional tolerances and superior surface finishes, yet traditional CNC machining workflows rely on static toolpaths that cannot account for real-world variation in workpiece positioning, material stock, or machine deflection. For Cincinnati-based SIXDIGMA, which specializes in advanced CAD/CAM and CNC integration for complex machining problems, the status quo meant time-consuming manual fixturing, repeated inspection cycles, and the risk of scrapping high-value aerospace parts when dimensional deviations were discovered too late in the process.

SIXDIGMA implemented a closed-loop adaptive machining workflow built on three integrated digital technologies from Siemens. At its core, Siemens NX CAM software generates advanced multi-axis toolpaths capable of achieving excellent surface finish on tight-tolerance aerospace parts. This is paired with 5-axis probing directly on the CNC machine, which accurately locates each workpiece without requiring specialized fixturing. The third element — the closed-loop feedback layer — uses in-process measurement data to validate actual workpiece surfaces against the CAD model and automatically modifies individual toolpaths before cutting. Siemens Sinumerik CNC controllers execute the adapted NC programs on a Grob machine tool, completing an end-to-end digital thread from design through verified cut. SIXDIGMA founder Edwin Gasparraj demonstrated the full workflow by machining a complex aerospace airfoil using this integrated approach.

The closed-loop adaptive machining process demonstrated by SIXDIGMA delivers measurable quality and workflow improvements for complex aerospace components:

• Eliminated special fixturing requirements — 5-axis probing locates the part in situ, removing setup time and the cost of dedicated fixtures for each component variant.
• Automated toolpath correction — the system detects surface deviations and modifies individual toolpaths automatically, reducing reliance on manual operator intervention.
• High surface finish on tight tolerances — NX CAM's advanced toolpath algorithms achieve the surface quality required for aerospace-grade airfoils.

While specific cycle time or scrap rate figures were not disclosed, the workflow compresses the traditional inspect-adjust-recut loop into a single automated pass, directly reducing the risk of late-stage part rejection.

• Combine probing and adaptive control — in-process measurement only delivers value when it feeds directly back into toolpath modification; the two capabilities must be integrated, not siloed.
• Fixturing is a hidden cost target — 5-axis probing can eliminate dedicated fixtures for complex parts, improving flexibility and reducing setup costs across part families.
• A digital thread requires compatible platforms — SIXDIGMA's success depended on NX CAM, Sinumerik controllers, and the CNC machine tool operating within a unified data environment.
• Demonstrate on a hard part first — validating the workflow on a complex airfoil builds confidence for broader adoption across other tight-tolerance aerospace components.