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Thread 218/05
Surface Finish Chart, N9 and N11
Q. I'm looking for a conversion chart for Machining Symbols. I currently have an Austrian Drawing with the following Machine Symbols Surface finishes: N9 and N11. I need to know what these are in our standards, Like a 32 or 63 Surface Finish. Please let me know if you have any luck.
Thanks,
machine works - Miramichi, New Brunswick, Canada
2003
publicly reply to Christopher Morrison
A. Take a look at finishing.com archives letter
7560 for that chart
This specification refers to Ra values. N1 = .025 micrometers or 1 Ra. N2 = .05 mm or 2 Ra.

AF Kenton
retired business owner - Hatboro, Pennsylvania
2003
publicly reply to AF Kenton
A. In order to understand N11, N11 , 32 , 63 Please visit:
www.roymech.co.uk/Useful_Tables/Surface_Texture/Sur_Fin_Values.html
- Aurangabad, Maharashtra, India
April 6, 2009
publicly reply to SHINDE UMESH
Q. Does the surface finish apply to all materials such as teflon or rubber materials or is it strictly for metals? Please advise.
Sandra sargent- dublin, California, usa
October 3, 2012
publicly reply to Sandra sargent
A. Hi Sandra. Those surface finishes are about the topography of the surface so they theoretically apply regardless of the material being discussed, but that might be a slightly misleading answer. The standards were designed in response to the issues involved in machining metals and utilizing metals, so they are probably not the best standards by which to describe the finish of materials like teflon and rubber which are manufactured by molding and which are flexible. Please see letters such as 20910, 24465 and 30763 where plastic surface finishing standards are discussed. Good luck.
Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
October 4, 2012
publicly reply to Ted Mooney
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