In “The Material Ratio Curve” we look at this rather well-known curve (historically known as the Abbott-Firestone Curve). It shows us the amount of material that we encounter as we move further down into a surface. That can tell us a lot about the surface: how durable it may be, how it could carry lubrication, … Read more
In “Rz (Average Peak-to-Valley Roughness)” we look at the world’s second most common surface texture parameter. Our eye can do a pretty good job of telling us the general roughness of a surface. Rz works similarly. One caveat: there are other definitions of Rz out there—we will show you the differences and what to look … Read more
The average roughness (or “Ra”) value of a surface is the most common number describing the “amount” of roughness on that surface. While the Ra value (or “Sa” for areal / 3D measurements) may give a general sense of the surface texture, it cannot distinguish between two surfaces of different shapes. For example, a jagged … Read more
In our last video, “Roughness and Waviness,” we looked at how to separate longer wavelength “waviness” from short-wavelength “roughness.” In “Bandpass Waviness” we go a step further and also separate waviness from the long-wavelength “form” shapes. Making this distinction lets us target the waviness features that could matter most to you. For example, if you … Read more
In this second Notepad Series video we look at the process of separating data into features that we will consider shorter-wavelength “roughness” versus longer-wavelength “waviness” for a given application. Seeing the process drawn out, step by step, can really clarify how the roughness and waviness profiles are created, and what they really mean.
When we talk about surface texture, what is roughness? Does the word “roughness” mean the same thing to everybody? The fact is, what we call “roughness” is entirely based on our application. This video shows why it is so important to specify the range of features that we will call “roughness” in any given situation.