Scientists and philosophers through the ages have struggled with the concepts of friction. Leonardo da Vinci studied many aspects of friction, bearings, etc. In one set of experiments, he tied a cord to a rectangular block and dragged it along a surface. He found, surprisingly, that dragging the block on its short side, or long … Read more
May 2 will mark the birthday of Frank Philip Bowden who, along with David Tabor, laid the groundwork for much of our modern understanding of friction and lubrication. “Putting two solids together is rather like turning Switzerland upside down and standing it on Austria—their area of intimate contact will be small.” – Frank Bowden Bowden … Read more
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
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
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
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