Plastic media provides a balance between effectiveness and part protection, making it ideal for softer metals (aluminum, brass, zinc, copper) and plastic components. It excels in pre-plate finishing, deburring die-cast parts, smoothing molded plastics before painting, and preparing surfaces for anodizing. Its lighter mass prevents impingement, edge damage, and dimensional distortion that heavier ceramic media can cause.

Plastic media is significantly lighter and gentler than ceramic. This makes it the preferred choice for soft metals like aluminum, brass, and zinc where minimal dimensional change is critical. Ceramic is more aggressive and better suited for hard metals (stainless steel, titanium, tool steel). High-density plastic media bridges the gap — it can match ceramic cutting rates without the surface peening or excessive edge rounding that ceramic can cause on softer materials.

High-density plastic media is a hybrid combining polyester resins with ceramic fillers, achieving ~95–100 lbs/ft³ density compared to standard plastic at ~60–75 lbs/ft³. It's formulated for harder metals like stainless steel, titanium, and nickel alloys where standard plastic lacks cutting power but ceramic causes unacceptable surface effects. It can reduce cycle times by up to 50% while maintaining surface integrity — a critical advantage in aerospace, medical, and defense applications.

Synthetic media uses a urea formaldehyde resin binder with microcrystalline silica. Its acidic pH (~3) enables micro-cutting action excellent for pre-plate surface preparation. Key advantages: virtually no surface residue, excellent stability in high-speed centrifugal systems, and clean non-foaming operation. Important: the acidic pH requires corrosion inhibitors when processing copper, brass, or other non-ferrous metals. Do not freeze synthetic media in storage.

Shape selection depends primarily on part geometry. Cones are the most versatile, providing uniform finishing on all surfaces except inside corners. Angle-cut triangles and tristars penetrate remote areas like gear teeth and slots. Cylinders work well on flat and concave surfaces. The golden rule for sizing: choose media that cannot lodge inside holes, slots, or recesses in your part. Smaller media (1/8"–1/4") suits precision parts with fine features; larger sizes handle general deburring. Contact us with your part details for a specific recommendation.

Yes — plastic media is one of the best choices for pre-anodizing aluminum preparation. It produces clean, uniform, burr-free surfaces required for even anodizing coverage and consistent dye uptake. Unlike abrasive ceramic media, plastic is far less likely to embed particles into the aluminum surface or alter surface chemistry. Grades R-600 and R-650 are commonly specified for aluminum pre-anodize work, followed by a thorough rinse cycle before the anodizing bath.