.jpg;width=70;height=70;mode=crop)
Editor-in-Chief, Modern Machine Shop
Share
Related Suppliers
Here is a probing routine in which a machining center performs its own first-article inspection. The machine first probes a known reference to overcome measurement error. The difference between the known measurement and the measured value becomes the offset that will correct the probe measurement. This difference also serves as an offset for correcting the machining moves for the next workpiece in this setup.
This video was shot at Renishaw, and shows an actual part of the company’s automated production process. Renishaw offers these additional comments about the “reference comparison” or “artifact comparison” technique:
Featured Content
• The probe is calibrated against an artifact that has been calibrated at 20°C with uncertainty traceable to NPL.
• The artifact is the same material as the workpiece.
• It has geometry and features similar to the part.
• Comparative measurement gives traceability, and is independent of machine tool measurement accuracy.
• The part is measured using gaging points on the surfaces.
• Thermal effects determined from the artifact measurement are compensated when updating the process variables.
RELATED CONTENT
-
Composites Machining for the F-35
Lockheed Martin’s precision machining of composite skin sections for the F-35 provides part of the reason why this plane saves money for U.S. taxpayers. That machining makes the plane compelling in ways that have led other countries to take up some of the cost. Here is a look at a high-value, highly engineered machining process for the Joint Strike Fighter aircraft.
-
How Accurate Is Your Machining Center?
Virtually every machine tool builder lists, as part of a machine's specification, accuracy and repeatability figures. What's generally not given is the method used to arrive at the figures. Though these methods are defined in linear positioning standards, not all builders use the same standards.
-
Do's And Don'ts For Keeping Dial Indicators In The Game
Just because dial indicators have been around since the early 1900s, don't expect them to fade away with the last century. This tool's long-term popularity is well earned.
