Digital Metrology Notepad Series - Stylus Tip Radius

Is a smaller stylus tip better for measuring roughness? Is a larger tip more durable?
The radius of the stylus tip influences what we see in surface texture measurement data. Most styli can measure longer-wavelength form and waviness. With finer scale (shorter-wavelength) roughness features, however, the radius of the stylus can have a big impact. Since every tip is a little different, the resulting roughness measurement values can be different even when you are trying to use the “same” radius.
To make sure that the data from different instruments and styli are consistent we employ a "short wavelength," filter. The short filter gives us the consistency we are looking for. In this video we will talk about how that filter’s cutoff is determined and what it means for your measurements.
We also look at the common misconception that a larger radius stylus is more durable than a smaller one. It's really not the case, and we will show you why.