In centrifugal disc finishing, choosing the right abrasive media is crucial for achieving the desired results. Here are some of the main types of media used and their characteristics:

1. Ceramic Media:

  • Ceramic pyramids: The most common type, ideal for deburring, radiusing, and achieving a satin finish. Available in various sizes and grits (abrasiveness levels).
  • Ceramic spheres: Used for polishing and achieving a smoother finish. Can be solid or filled with abrasives for higher performance.
  • Ceramic cylinders/chips: Suitable for intricate shapes and delicate parts due to their softer impact. Good for cleaning and light finishing.

2. Plastic Media:

  • Plastic pyramids/cones: Similar to ceramic pyramids but gentler on softer materials like plastics and aluminum. Used for deburring, radiusing, and light polishing.
  • Plastic spheres/cylinders: Ideal for polishing and burnishing softer materials. Provide a gentler action and minimize scratching.
  • Composite plastic media: Combinations of plastic and abrasives for specific applications, such as high-gloss polishing or cleaning specific contaminants.

3. Other Media Types:

  • Natural stones: Corn cob media for gentle cleaning and polishing of delicate parts. Walnut shells for removing heavy oxides and contaminants.
  • Vegetable-based media: Eco-friendly alternatives made from rice bran or other organic materials. Suitable for gentle cleaning and polishing.
  • Magnetic media: Used in conjunction with magnetic separators for easier media recovery and separation from finished parts.

Choosing the Right Media:

  • Consider the material of your parts: Harder materials like metals can handle more aggressive ceramic media, while softer materials like plastics require gentler plastic or even vegetable-based options.
  • Desired finish: Rougher media like pyramids are good for deburring, while smoother spheres or cylinders are for polishing. Choose the grit size based on the initial surface roughness and desired final finish.
  • Part geometry: Intricate shapes might require smaller media or softer options to avoid damaging delicate features.

Additional factors:

  • Media size: Smaller media works well for intricate areas, while larger media provides a more aggressive finishing action.
  • Density: Heavier media can exert more pressure for faster results, while lighter media might be preferred for delicate parts.
  • Cost and reusability: Consider the cost per use and how long the media lasts before needing replacement.

Please consult with a Bel Air finishing expert to help you select the optimal abrasive media for your specific needs and application.