CHOOSING THE RIGHT TUMBLING MEDIA FOR SURFACE FINISHING

Tumbling media is the work horse of CBF and vibratory finishing. Regardless of the industry or the job at hand, using the right media is paramount to ensuring a finish meets exact standards and requirements.

WHAT IS TUMBLING MEDIA?

Media is rigid shaped segments or pieces which have been molded, sintered, cut or extruded into various shapes and sizes, typically containing bonding agents or abrasives.

HOW DOES TUMBLING MEDIA WORK?

Media is combined with parts, water and surfactant in a CBF barrel or vibratory bowl/trough. As energy is created within the barrel or bowl, the parts and media rub against each other, refining the surfaces of both the part and media. New abrasives are exposed in the media as they wear down to ensure consistent material removal.

COMMON MEDIA TYPES & USES

The most common media types include ceramic, porcelain, plastic, steel and organic compounds – such as corn cob or walnut shell. Each type of media produces a different finish:

• CERAMIC – With a relatively high density, ceramic media is ideal for hard and heavy metals such as titanium or stainless steel but can also be used on plastic and aluminum. It is used for general-purpose cutting and rust removal.
• PORCELAIN – Technically a type of ceramic media, porcelain is commonly used to achieve a higher gloss polish/finish.
• PLASTIC – Softer or malleable metals, such as aluminum, brass, and zinc are commonly a good match for plastic media. With its relative ease to manufacture, durability and water-resistant properties, plastic media is a cost-effective option used for tumble deburring, precision deburring, deflashing, burnishing, and pre-polishing.
• STEEL – Made from hardened carbon and stainless steel, steel media is used for shining, polishing and burnishing of materials and applies heavy pressure to deburring of steel parts. Steel media has a slow wear rate and can be used multiple times.
• ORGANICS – Organic media, including corn and walnut shells have multiple uses. Not only used to dry parts after wet finishing, organic media can also be combined with polishing paste, to produce a high gloss finish on materials such as stainless steel, aluminum and acrylic.

MEDIA SHAPES

Media comes in a variety of shapes, each with a different purpose. Spheres, ovals and cylinders wear evenly, chip less frequently and are less likely to become lodged in parts. Cones, stars, pyramids and wedges are ideal for complex parts with hard-to-reach geometries, despite wearing and chipping at a higher rate.

SELECTING THE RIGHT SIZE & SHAPE

There are many factors to consider when selecting media – including the part’s material type, size, and shape – along with a media’s ability to produce the required finish. Smaller media size offers a more detailed and smoother finish but takes longer to complete due to its reduced mass. A larger media size offers a quicker processing cycle but creates a rougher surface. Occasionally, more than one media type or size may be needed to achieve the final result.

UNIFORM RESULTS

The experts at ISO Finishing are experienced in selecting the right media to achieve the right finish. We have the proven ability to customize surface finishing solutions on any material which is documented and repeatable. The best way to show you how our finish will be your finish is to process your sample. Let us show you what we can do.

LET’S GET IT FINISHED.