Mass finishing is a general term that workpieces surface treated either in vibratory finishing machine, centrifugal disc finishing machine or centrifugal barrel finishing machine etc together with tumbling media and compound to achieve desirable finishing performance. The benefit of mass finishing process including deburring, polishing, ball burnishing, edge rounding, cleaning, smoothing and de-rusting.
Deburring is the most important application in the mass finishing process. Burrs come from machining, cutting, milling, stamping, turning as well as other manufacturing processes. The parts geometry, material, burr properties are important to design deburring process. Parts with better starting condition can save a lot to make deburr. If the burr size is too thick or large, we required wheel grinding or other processes before deburring with mass finish solution.
2. Polishing: offer luster surface
The polished or luster surface is critical in the automotive industry where style and aesthetics are important. The polishing surface improves the light reflecting properties of parts on the surface. An application is chrome bumpers in automotive. The right combination of polishing compound together with tumbling media is the key to success.
3. Ball burnishing: fast and economical process
Ball burnishing is the process to produce smooth, mirror-like finishes on parts. Metal surfaces vary greatly, from matt finish to smooth and polished surface where surface reflective is improved. The ball burnishing process is a fast and economical process which take place in either round vibratory finishing machine or tub vibrator with curved wall design.
4. Radiuasing: Edge rounding and blunting
The sharp edge of workpieces in commercial use will cut hands, containers or nearby components in normal handling, installation, or repair. Even though the edge is burr free or without extra material, the user doesn’t want the sharp edge in many applications. Those edges need to be radiuasing or edge rounding with mass finishing process.
5. Cleaning & degreasing: cleans oily and dirty surface
A major benefit of mass finishing is its ability to clean parts while it smooths and deburrs them. Soaps and other cleaning compounds can mix together with polishing media to clean workpieces surface in one step process. The consistent drain on dirty water and adding new water/compound can improve workpieces surface greatly.
6. Smoothing: Surface finishing with either smoothing or roughen
With normal processing, surface finishes improve in mass finishing operations. A mild steel workpiece can start with a surface roughness Ra 6.35 and roughness value end up with Ra 0.2 with centrifugal barrel finishing machine in a couple of hours.
Besides, finishes can be roughened when necessary by a fast cutting ceramic media to make matt finish. The matt finish is desirable to increase the adhesion strength of coatings or improve frictions of parts.
7. Descaling & Derusting: Remove thin oxides and heavy rust scale
Mass finishing removes heat-treat scale and discoloration in the same operation in which is deburrs parts. Whether it is the blue tint of heat treatment, a straw brown color, descaling and de-rusting process can remove these imperfections. If the scale is very heavy, surface finishes are not good as they need machining.