3D Surface Roughness and Wear Measurement, Analysis and Inspection

Typical Average Roughness values for various machining operations

Ra (Roughness Average, or average roughness) is the average height of all measured points on a surface. Ra is the most widely used surface texture parameter. As we’ve mentioned elsewhere in this blog, there is much information about a surface that Ra cannot provide. It can, however, be a fast, simple way to tell whether a … Read more

Choosing an interferometric objective

Though an optical profiler and stylus measurement system are very different technologies, they do also have some similarities. If you are used to working with stylus-based measurement systems, you know that the length of the dataset is determined by the evaluation length, while the size of the stylus tip is related to the smallest features … Read more

Wear means “material removal”…doesn’t it?

When we think of how to measure wear, the first thought might be to quantify how much material has been removed from a surface. We might look at a change in average roughness, say, to get a sense of how much peak material has been removed through contact with another surface. Or, we may use … Read more

Average Roughness basics

average roughness, ra, average roughness symbol, average roughness surface texture parameter

How do I measure Ra 32? or 32 Ra? or 32? Average roughness (Ra) is the tip of the deep and complex world of surface texture analysis. As you’ll see throughout this blog and many excellent books, we have many tools today that we use to measure surface texture, and hundreds of ways to analyze … Read more