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Surface Roughness Conversions




I'm looking for a conversion table for surface roughness between Ra and Rz for common metal removal processes such as milling and turning. Any help would be greatly appreciated.

Joe Reames
- Charlotte, North Carolina
2000



Joe:

Go to this URL. I have found this site to be a good source for surface parameter info.

www.predev.com/smg/parameters.htm

Good Luck,

Bill Boatright
- Raleigh, North Carolina
2000


They are based on two different measuring criteria. So you can not convert one to the other like Ra to RMS. Ra is the average of all the peaks and valleys. Rz is the average of 5 of the highest peaks and 5 of the lowest valleys.

Todd Osmolski
- Charlotte, North Carolina, USA
2000


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