“What is filtering?” “What is waviness?” “What’s causing my surface to fail?”
Carl Musolff and Mark Malburg put together The Surface Texture Answer Book to answer these types of questions in one easy-to-use reference. The Q&A-style book addresses more than 100 of the most commonly-asked concerns regarding measurement, analysis, interpretation, specification, and application of surface texture.
The information is aimed to help technicians and engineers to quickly address their questions, regardless of their level of experience with surface analysis. With hundreds of informative figures and images, the book is also a valuable learning resource as well as a problem-solving guide.
Most of this information throughout the book is never taught in school, so there is a real need for direct answers presented in a non-academic way. Most answers are just a few pages long—while hundreds of figures to do the heavy work of explaining complex topics in a short space.
The book draws on numerous resources, as well as the authors’ own industry experience. Topics focus primarily on two-dimensional measurement techniques, which represent the vast majority of surface texture measurements in industry today. The book also touches on some important aspects of 3-dimensional (areal) measurement, which is becoming more prevalent in development and industrial applications.
Carl Musolff is an industry veteran with over forty years of experience in product development, wear analysis, failure analysis, materials, metallurgical engineering, and surface texture analysis and specification. He’s worked on thousands of projects to improve performance and longevity across a variety of components and applications. Carl is deeply immersed in understanding surfaces from the functional perspective, and he has drawn on his passion for teaching to mentor dozens of engineers and technicians.
Mark Malburg is the president of Digital Metrology Solutions. With over 30 years in applied surface metrology, he is the chief architect of a range of standard and custom software for surface texture and shape analysis. Dr. Malburg has consulted in numerous industries ranging from optics to aerospace. He is a regular participant in National and International standards committees and has helped shape many of the standards that govern surface specification and control.
The following topics are answered in The Surface Texture Answer Book:
- How does a roughness measurement system work?
- Is the world moving to optical 3D measurement systems?
- When should I use 3D (areal) instead of 2D (profile) measurements?
- Will my 2D stylus system correlate with my 3D optical system?
- What should I consider when buying a surface measurement system?
- Should I buy a used instrument?
- Which measurement stylus should I use?
- What do skidded and skidless mean? Which should I use?
- Which skid configuration should I use? Skid radius? Skid position?
- Why are my skidded roughness results higher than I expect?
- How does the stylus reach the bottom of deep valleys?
- Does the stylus tip radius make a difference?
- Will the stylus scratch my surface?
- Can a diamond stylus be damaged? How can I tell?
- What are data spacing and data density?
- How fast can I measure?
- How long should a measurement be?
- Can I evaluate roughness, waviness, and shape with one long trace?
- I have a short feature. Do I still need five sampling lengths?
- Why do I have to measure 4.8 or 5.6mm to get a 4mm evaluation length?
- How many times should I measure my part?
- I see unexpected things in my data. Are they real?
- How much noise can I tolerate in my measurement system?
- How do I get noise out of my measurement system?
- How important is sample alignment when I make a measurement?
- Why does a cheap instrument repeat better than an expensive one?
- Can I do a gage R&R study on a surface texture instrument?
- How do I perform a surface texture measurement uncertainty study?
- How can I lower my instrument’s measurement uncertainty?
- How does surface variation impact my measurement results?
- How do I know if my instrument is capable of measuring my surfaces?
- What if my supplier’s instrument doesn’t correlate with mine?
- How do I compare measurements between two instruments?
- My supplier is measuring higher values. Should I adjust my tolerances?
- Can I just measure roughness with my fingernail?
- Can I measure surface texture on my CMM?
- What is form removal?
- What is “filtering?”
- How is a filter used to separate roughness from waviness?
- What do all of those parameters mean?
- What is the zero line in my profile graph based on?
- How do I decide which type of filter to use?
- My system has different Gaussian filters. Which should I use?
- How do I decide whether to use the Gaussian or the spline filter?
- When should I use the robust filter?
- Should I use the robust filter for everything?
- When should I use the valley suppression filter (ISO 13565-1)?
- Should I use the “ISO” filter on my system?
- What is a 2CR filter? Should I use it?
- What is the difference between Phase-Corrected and Gaussian filters?
- If a cutoff wavelength is not specified on my drawing, what should I use?
- Why does my instrument only have certain cutoff values?
- Why is five the default number of roughness sampling lengths?
- How many data points should I have in my measurement?
- How do I know if my data is accurate?
- What can I learn about the manufacturing process from a surface texture trace?
- Why do my roughness traces show metal that I can’t polish away?
- Why don’t my traces look like the photos of my surface?
- I have an Rz requirement. Can I just scale my Ra result to get an Rz?
- My supplier consistently reports values of Rz smaller than mine. Why?
- Should I be concerned with waviness?
- Why do parts measure the same but function differently?
- My instrument reports roughness and waviness. Where is form?
- How do GD&T and surface texture specifications relate to each other?
- Which parameters should I use to detect scratches and dents?
- What does 300:1 or 100:1 mean on my printouts?
- What does “max” mean in a surface texture callout?
- How do I implement the 16%-rule in practice?
- How do I specify surface texture requirements on a drawing?
- How do ISO and ASME surface texture callouts differ?
- How do I specify information that is not covered in the standards?
- How do I specify trace location and direction on a drawing?
- On older technical drawings, what are the numbers above the radical?
- What do triangles mean on a drawing?
- How do I specify the measurement of smaller features?
- Most drawings only specify Ra. Is that enough?
- How can I measure roughness in grooves?
- How can I measure roughness in a fillet radius or corner?
- How do I measure a surface that my instrument cannot reach?
- How do I measure lay?
- How do I control peaks on a surface?
- Can I measure around a cylinder instead of along its axis?
- How do I measure the amount of wear on my surface?
- My part is curved. Can I measure it?
- My part is curved. How do I detect bumps within the curvature?
- Why does my gasket leak even though the roughness is correct?
- Which parameters should I use to describe a plateaued surface?
- My surface is porous. How can I control the roughness?
- Which parameters specify surfaces with functional requirements?
- Which parameters relate to load carrying ability?
- Which parameters relate to lubricated interfaces?
- Which parameters relate to sealing?
- Which parameters relate to noise and vibration?
- Which parameters relate to appearance?
- Which parameters relate to coating adhesion?
- Which parameters should I use to control my processes?
- How do I create a surface texture specification?
- Does my surface contain tears, burrs, or folded material?
- Can texture distinguish material properties from machining properties?
- Can I measure grinding damage via surface texture analysis?
Definitions and Terminology
- What do R, W, and P stand for in the parameter designations?
- What is waviness?
- What is a transmission band?
- Are “cutoff” and “sampling length” the same thing?
- What is bandpass analysis? Why would I need it?
- What is a morphological filter? What is it used for?
- What is the difference between Rp and Rpm?
- Should I use Rsk or Rku to specify my surface roughness?
- What is material ratio?
- What is the material probability curve and what is it used for?
- Why can’t I find the tp parameter on my system?
- Which parameters measure width or spacing rather than height?
- What are height and width discrimination and what are they used for?
- What are the motif parameters?
- What are fractal methods in the context of surface analysis?
- What are “vertical range” and “resolution”?
- What is the autocorrelation function?
- How do I know which wavelengths are in my surface data?
Surface texture is more than just a number from a measurement device. It’s a microscopic world with huge implications for many industries and applications. Because it’s such an important topic, the authors wanted to make a book that clarifies the concepts, and misconceptions, relating to surface texture.
We hope you will pick up a copy, perhaps at first for a particular answer, then maybe find other topics along the way that expand your knowledge as well.
The 400-page paperback book is available through amazon.com.