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Rz finishes by production method ?

I'm in the process of completing a design for a client that prefers to specify surface finishes using Rz, which I understand doesn't convert simply to Ra. Is anyone aware of data regarding Rz surface finishes obtainable by various production methods ? (A chart similar to the commonly found ones based on ASME B46.1, but in Rz instead of Ra, would be ideal.)

Scott Flagg
- San Antonio, Texas
2003

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This question comes up about once every 2 or 3 months. Rz is almost the same as RMS, except it is a new ISO spec that requires at least 10 points or 5 peaks to be measured with a profilometer. Ra and RMS are not a constant, but for a quick rough reference divide by 4.

AF Kenton
retired business owner - Hatboro, Pennsylvania
2003