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Want a visual Ra comparison chart

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I am looking for a visual comparison chart for Ra surface finish values.

Gary Merkel
tool & die - Richfield, Wisconsin

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First of three simultaneous responses -- ++++++

You will find comparator metallic plates. They can be either manufactured to your specs or according to vendor's standards in stainless steel, vacuum or galvanoformed.

Guillermo Marrufo
Monterrey, NL, Mexico

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Second of three simultaneous responses -- ++++++

A visual "Ra" chart is going to be terribly subjective. Light reflection can be seriously different between straight line sanding and single point machining, grinding and dual action sanding, and blanchard grinding.

James Watts
- Navarre, Florida

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Third of three simultaneous responses -- ++++++

McMaster-Carr will sell you a comparator sample plate, or any good tool supply company.

Jeffrey Holmes, CEF - Spartanburg, South Carolina

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++++++ I agree with James from Florida. Your best bet is to just break down and buy either a surface gauge or profilometer. Way too many variables. Brandt Hinton - Elk River, Minnesota ANSWER or FOLLOW UP POST an unrelated QUESTION HOT Topics

Profilometer

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