Latest Notepad Video: Average Roughness (Ra)

The fourth video in the Notepad Series from Digital Metrology Solutions has been released.

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 surface with sharp spikes could have the same Ra value as a smoothly plateaued surface with lots of deep porosity. As shown in this video, describing a surface using only Ra is like describing a concert only by loudness! Yet, Ra (or Sa) may still have its uses in some production settings.

“This new video series is designed to introduce casual users to surface analysis,” said Mark Malburg, President of Digital Metrology. “Many technicians, researchers and engineers rely on surface data but only have a passing knowledge of how to explore and understand a surface. Slides, equations, and theory can sometimes get in the way. Each of these videos presents a single topic in just a few minutes. We take a concept down to the level of a simple drawing in real time, which provides an incredibly effective path to understanding.”

The Notepad Series departs from the typical web-based seminar content. “The Notepad Series flips this model upside down. The sessions are brief, informal, free, and there is no commitment or registration required for viewing.”

Malburg added that the videos serve as a catalyst for further training. “These videos elevate the basic knowledge level and make dedicated training/consulting more accessible and more effective.”

The Notepad Series videos are available at New videos follow every few weeks.