The following charts and tables convert surface finish or roughness between selected industry standard units. Where: Cut-Off Length = Length required for sample. Conversion math at bottom -- μ=0.000001m=0.001mm. μin=0.000001 in=0.0254 μ. Conversions (math): Example: Surface Roughness Value Equivalents.

Surface roughness is a calculation of the relative smoothness of a surface’s profile. The numeric parameter – Ra. The Ra surface finish chart shows the arithmetic average of surface heights …

Jul 14, 2020 · A standard #4 finish has an Ra of about 0.8 µm (32 µin), while a #4 Dairy or Sanitary finish has a roughness average between 0.3 µm (12 µin) and 0.4 µm (16 µin).

Mar 11, 2019 · Shows that’s a 32 finish can be achieved by feeding .0049 per rev with a 1/32” nose radius tool. Yeah as long as you have your cutting speed up high enough you can pretty easily turn a 32Ra finish. If it's not quite shiny enough give it a quick spin with lightly oiled brown scotch-brite and it will look pretty damn good.

Jul 26, 2023 · The typical surface roughness is 32 micro inches or a surface finish of 32. It is equivalent to 1/32 inch to have a 32-micron roughness. The surface finish that is smoother and closer to a 32 finish is a 6-surface finish. What differentiates Ra and Rz in the surface roughness chart? Ra represents the average distance between peaks and valleys.

So, what are the units of a “Ra 32” surface? An Ra of 32 µ-in would be typical of a machined surface, such as a brake rotor. An Ra of 32 microns, however, would be more like the surface of brick!

Ra (Average Surface Roughness) is a unit for measuring surface finish, and it is also referred to as Center Line Average or Arithmetic Average. It is the average roughness between a roughness profile and the mean line. This is the commonly used parameter for surface finish.

Dec 18, 2024 · A 32 Ra surface finish is a common specification in the aerospace, automotive, and medical industries. It indicates that the surface roughness of a material is approximately 32 micrometers (μm) on average.

No. 4 Standard Satin Finish (32 Ra Max), also known as the ‘workhorse finish,’ is one of the most common finishes for architectural and processing vessels. The satin grain appearance is easily blendable and meets strict sanitary requirements.

Feb 14, 2025 · A 32 surface finish is often expressed in microinches and corresponds to a surface roughness of 0.8 µm (Ra). It is typically used in applications that don’t require a high degree of smoothness but still need moderate quality, such as in manufacturing equipment.