VIDEO: Removing Tool and Machine Marks with Scotch-Brite™ Precision Surface Conditioning Discs

Today we'll be blending and removing mill marks on aluminum. We will remove imperfections and merge the repaired section with the surrounding surface. Mill lines seen here are the result of using a rotary cutter to cut, shape, or remove material from the work piece. Milling is a normalized process in industry and machine shops today in order to process parts to a specific shape and size. There is a variety of reasons why operators blend the mill marks such as burr removal, preparing the surface for paint, removing residual stresses, and/or providing the aesthetic uniform finish.

This is commonly seen in aerospace machining operations. A larger footprint of a disc is preferred in instances such as this to minimize undercutting. In certain locations, blending of the mill marks include an edge break and radius operation which Scotch-Brite Precision is well suited for. When going over an edge, have the rotation of the disc flow off the part to extend the life of your surface conditioning disc and to maintain more control over the process. Scotch-Brite Precision is now available in five grades–very fine, fine, medium, coarse, and extra coarse. Today we are using the medium. For high-pressure applications that may include parts with tabs, narrow protrusions, and other complex geometry, the Scotch-Brite offers SE and light grinding and blending surface conditioning discs that are designed for durability.