## What Ra is a 2B finish?

Depending on its gauge (thickness), factory-fresh 2B-finished stainless steel typically has an Ra value ranging from 0.3 micrometers (. 0003mm) to 1 micrometer (. 001mm). Proper electropolishing can decrease the Ra of the surface to between 4 and 32 microinches depending on the gauge (thickness) of the metal.

What Ra is 180 grit?

Surface Finish Charts

Standard Grit (reference only) Ra µin RMS µm
150 27 – 32 0.76 – 0.89
180 16 – 23 0.51 – 0.64
240 14 – 18 0.38 – 0.51
320 8 – 10 0.23 – 0.28

What does a 6 Ra finish look like?

A 6 Ra (µin) is a very smooth polished surface. Actual surface profile showing the Ra surface finish of 0.164 µm (6 µin microinch) on a ground & polished steel bar. The photo of the ground & polished steel bars show what the surface finish looks like when visually looking at the surface.

### What are Rara and D surface finish units?

Ra and D are two important surface finish parameters… The Surface Finish Units we would use for parameters like Ra would be either micro-inches (English or Imperial) or micrometers (Metric). Our chart of surface finishes by manufacturing process (see above) gives both. When we try to measure a surface finish, the methods fall into three categories:

What is the surface roughness of 40 microinch of Ra?

Ra to Rt: 1.0 micrometer Ra x 8.7 (Rt Factor) = 8.7 micrometer Rt 40 microinch Ra x 8.7 (Rt Factor) = 348 microinch Rt Surface Roughness Value Equivalents

Why is surface finish and Ra important?

Surface finish and Ra are important to steel bars, shafts, and chrome plated hydraulic cylinder rods.  It will influence qualities such as the lubrication, ability to hold pressure, friction, resistance to corrosion, noise reduction, and visual appeal to name a few.