Geometry precision

Jun 12, 2024 | 2 min to read
Geometry precision

Squareness: This refers to the perpendicularity between two axes. If the machine’s axes are square, it means that they are at right angles (90 degrees) to each other. This is crucial for ensuring that the machine can accurately produce parts with right angles and proper geometric alignment. 

Flatness: This refers to the evenness of a surface along a single plane. For CNC machines, flatness ensures that the working surfaces, such as the table or the bed, are even and do not have any high or low spots. This is essential for maintaining accuracy in the vertical plane and ensuring consistent cutting depths. Yaw:


Yaw: is the rotation around the vertical axis (Z-axis). A yaw error means that the axis deviates from its intended path horizontally. For example, if the X-axis yaws, it will cause the tool to deviate left or right along the Y-axis.

Pitch: is the rotation around the horizontal axis perpendicular to the direction of travel (typically the Y-axis or X-axis, depending on the machine orientation). A pitch error means that the axis deviates up or down along its travel path. For instance, if the X-axis pitches, the tool will deviate vertically along the Z-axis.

Roll: is the rotation around the axis of motion itself (the primary axis in question, usually the X-axis or Y-axis). A roll error means that the axis twists along its length. For example, if the X-axis rolls, it causes the tool to tilt side to side, potentially causing the machined surface to be uneven.

These angular errors can affect the precision and accuracy of the machined parts. Proper alignment and calibration of the CNC machine are essential to minimize yaw, pitch, and roll deviations. Regular maintenance and use of precision measurement tools, like dial indicators and laser alignment systems, can help ensure these errors are kept within acceptable limits. This will be explained in the next article.