In 2024, we were honored to receive a Massachusetts Manufacturing Accelerate Program (MMAP) grant, enabling us to acquire a Zeiss Coordinate Measuring Machine (CMM) equipped with Zeiss Calypso software. After a year of continuous operation, we’ve gained substantial insight into its capabilities. In this blog, we share key learnings from our experience.
Best Practices Embedded in the Zeiss Calypso Software
The implementation of the Zeiss CMM with Zeiss Calypso software has taken our quality assurance processes to a new level. Beyond the exceptional accuracy of the CMM (capable of measuring to the micrometer range), the Calypso software has QA best practices built into functions. This combination has enhanced our proficiency in measuring Geometric Dimensioning & Tolerancing (GD&T) features and provided new perspectives on circular geometries and flatness.
Enhanced Confidence Measuring GD&T Features
GD&T is a standardized framework for defining the size, form, orientation, and location of part features, ensuring proper assembly and function. In prototype machining, measuring GD&T features poses challenges, as the allowable tolerance of the feature being machined can depend on the accuracy and location of features that will be machined later in the process.
Our Zeiss CMM and Calypso software helps to address this challenge by measuring all part features and calculating whether the resulting combinations meet GD&T requirements. Prior to utilizing our new CMM, we relied on empirical estimations to assess GD&T compliance.
Understanding Circularity Beyond Basic Geometry
In high-school geometry, a circle is described by its radius.
In basic machine shop applications, a circle is described by its radius and tolerance.
Our customers often require tolerances approaching the limits of CNC machining capabilities, necessitating precise assessments of the roundness of cylindrical features. Variations in diameter or roundness can affect the fit and performance of components, influenced by factors such as material stresses, workholding deflection, and movements during subsequent operations. The Zeiss CMM provides graphical representations of round features, enabling us to identify and mitigate factors causing deflections.
When tolerances are at the edge of machine shop capabilities (typically around 0.0005 inches), different methods of measuring roundness are employed, each suitable for specific applications. Our new system enables us to provide three different methods for reporting the diameter of a cylinder, depending on it’s intended function:
Least Squares Method
The Least Squares Method calculates the radius by averaging measurements around the circle. This standard method is suitable for determining the diameter of circles without tight tolerances or mating requirements.
Maximum Inscribed Element
The Maximum Inscribed Element method identifies the largest circle that fits within the machined circle, appropriate for internal diameter (ID) features intended to accommodate another part internally.
Minimum Circumscribed Element
The Minimum Circumscribed Elementdetermines the smallest circle into which the part can fit, suitable for outside diameter (OD) features designed to fit into other components.
Enhanced Visibility into Flatness
Ensuring parts meet flatness requirements can be a challenge due to in inherent stresses in materials. Previously, flatness was measured manually, but with our new CMM, we obtain detailed flatness maps like the one shown below to pinpoint areas needing correction, significantly improving our quality control and precision.
By integrating the Zeiss CMM and Zeiss Calypso software into our operations, we’ve elevated our measurement accuracy and deepened our understanding of GD&T principles, leading to enhanced product quality and customer satisfaction. We have invested in training for our quality assurance staff and machinists to make full use of our CMM and the resulting data. The quality and efficiency results have been dramatic for our team and our customers.
Contact us to learn more about these topics or to discuss how we can use our industry best-practice QA capabilities to ensure the quality of your next project.