Mechanical Surface Finishing Processes Chapter 16

Finishing vs other final processes Finishing processes are not intended to significantly change the dimensions of the product. Finishing processes are intended to: Achieve closer tolerances Provide a protective coating Improve the appearance of the part

Surface Preparation Deburring Stripping/Cleaning Hand Barrel and vibratory Belt or disk sanding Stripping/Cleaning Dry and wet blasting Power Brushing Ultrasonic cleaning

Smoothing Operations Honing Superfinishing Lapping Abrasive stones Finish auto cylinder walls Superfinishing Chrysler Corp version of honing Lapping Removes less than 0.0005 inch (0.01 millimetre)

Polishing Fine scale abrasion Smearing Push high points over into the low places to smooth out the surface.

Buffing Used to produce a high luster Remove scratches from the surface Often precedes polishing Gives a smooth lustrous surface, Polishing puts the shine on the part.

Burnishing Brush the surface with a wire brush Uniform smooth finish Dull surface

Ballizing Forcing a ball through a hole slightly cut undersize. The ball passing through the hole Hardens Sizes Smoothes

Bearizng Used on larger holes than ballizing Roller bearings are mounted similar to honing stones Sizes Work hardens the hole.

Finish Specification Information needed See page 324 Process of final manufacturing operation Waviness, roughness and lay required Process of the surface prep or finish Type of coating to be applied Process to apply the coating See page 324