Path:Domestico >> Resources >> Plastic Surface Finish
  • Surface roughness is the measure if the finer surface irregularities in the surface texture. These are the result of the manufacturing process employed to create the surface. Surface roughness Ra is rated as the arithmetic average deviation of the surface valleys and peaks expressed in microinches or micrometers. ISO standards use the term CLA (Center Line Average). Both are interpreted identical.
  • The ability of a manufacturing operation to produce a specific surface roughness depends on many factors. For example, in end mill cutting, the final surface depends on the rotational speed of the end mill cutter, the velocity of the traverse, the rate of feed, the amount and type of lubrication at the point of cutting, and the mechanical properties of the piece being machined. A small change in any of the above factors can have a significant effect on the surface produced.
  • SURFACE ROUGHNESS AVERAGE OBTAINABLE BY
    COMMON PRODUCTION METHODS

  • PROCESS

    ROUGHNESS HEIGHT RATING MICROINCHES

     2000    1000    500     250    125    63    32    16     8     4    2    1    0.5

    Flame Cutting

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    Sawing

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    Drilling

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    EDM

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    Milling

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    Broaching

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    Reaming

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    Laser

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    Burnishing

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    Grinding

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    Honing

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    Polishing

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    Extruding

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    Investment Casting

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    Perm Mold Cast

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    Die Casting

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