In CNC machining, air cuts refer to any motion where the cutting tool moves without engaging the material. While some air cuts are unavoidable, excessive non-cutting movements lead to increased cycle times, reduced efficiency, and unnecessary tool wear. Understanding the different types of air cuts and their causes is essential for optimizing tool paths and improving machining productivity.

Types of Air Cuts
1️⃣ Touch Moves (Clean-Ups)

Touch moves occur when the cutting tool makes contact with the stock material but does not remove any material. These movements can be intentional, such as in finishing passes where the tool follows the contour for surface refinement. However, in some cases, they may be needles, adding unnecessary time to the process without improving the final part.

2️⃣ No Contact Moves

These air cuts happen when the cutting tool moves without touching the material at all. This often results from CAM-generated tool paths that fail to account for the evolving stock geometry. Since CAM software calculates tool paths based on the initial workpiece shape rather than the actual material left after each operation, unnecessary non-cutting moves can be generated. These ineffective motions waste valuable machine time and can be minimized by optimizing stock recognition settings in CAM software.

3️⃣ Unnecessary Home Returns & Distant Retracts

During operation changes, the cutting tool may retract to the home position or move to an unnecessarily distant location before starting the next operation. While some retracts are necessary for tool changes, excessive movements slow down the machining process.

Why Minimizing Air Cuts Matters
💡 Shorter Cycle Times – Eliminating unnecessary tool movements leads to faster machining and increased production capacity.

💡 Increased Efficiency & Cost Savings – Optimized tool paths reduce wasted energy and material handling, directly improving the overall cost-effectiveness of CNC operations.