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-----Difference between Ra and Rc - surface roughness
Q. In surface roughness measurement, we basically use two units Ra and Rc. Basically what is the difference between the two?
DIPAK NANDImachine shop engineer - Ahmedabad, Gujarat, India
Hi, Dipak.
I've never heard of an Rc scale for surface roughness. The only Rc that I am familiar with means "Rockwell C scale" -- a measure of hardness.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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March 16, 2011
A. In the thin air of the Rocky Mountains, Rz sounds a lot like Rc.
Some very good info here: https://www.taylor-hobson.com/faq.php
(Reposted from CR4)
- Colorado Springs, Colorado
A. Ra and Rc are similar measurements with different scopes. Ra is the arithmetic mean of the deviations of crests/troughs in a surface height, whereas Rc is more isolated, measuring the mean deviation of a given band of measured surface. To simplify, Rc is a shorter measure distance.
Charles LambertPool Designer - KC, Missouri
January 26, 2023
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