What materials can be used in tumble deburring? 

Visiting the ocean is incredible to experience. The air, the waves, whether it’s a cold morning or a hot summer day, the senses are amplified for a pleasurable time. Beaches vary and size, sounds and typography of the coastline. With high rocky cliffs or subdued gentle rolling mounds of seagrass you see sand as part of this landscape. Sand comes in different colors and textures depending on the geology and marine life in the area. What is common regarding sand on beaches is that this has formed in part through weathering. This process of agitation by waves, wind and sometimes ice breaks up rocks and seashells into smaller pieces creating the fine particles we call sand. It does have different textures worldwide but in all, if you can look at grains of sand, you will see the rounded edges, the smooth surfaces and different grain sizes. This takes millennia to occur and is constantly in motion but is a good example of what is called in industry, a tumble deburring process. Tumble deburring is often used as a post process for the manufacturing of precision parts.  

Tumble deburring is what is called a finishing process to enhance the surface quality of machined parts, both metallic and plastic. Using media of different types of organic and man-made materials results in the deburring or removing of rough and sharp edges that are often a result of precision parts manufacturing. These burrs and blemishes can lead to failures in the function of parts. They can aggravate the wear through friction and be harmful to bodily tissue if used for medical implants or other uses in medicine if not removed. 

Sometimes referred to as barrel tumbling, this method has its origins perhaps thousands of years ago. The agitation of media such as sand, or rocks would have been used to polish other stones for jewelry or perhaps to polish other tools. Today, modern machines employ a host of different media types in varying sizes, shapes, and abrasiveness to deburr materials like stainless steel, tungsten, aluminum, titanium, copper, brass, plastics, and others. 

• The size of the part coincides with the media size being used. Too large can damage smaller delicate pieces while smaller media can get lodged in a larger part and deform and cause wear to an unintended area. Deburring media can be as small as grains of sand to larger steel media and even organic use of walnut shells and rice. 
• The shapes of media used in deburring do vary greatly. You will find shapes used for specific types of end results: 

• Cones, angled tri star, and pyramid shapes are good for use on precision parts that have smaller angled features and hard to reach areas.  
• Cylinder shapes are used because they can pass through holes easily and smooth both the surface and inner walls of features. 
• Round and oval shapes are good in general but cannot reach smaller areas if the media size is too large. Careful selection of media size is important for all shapes and sizes for deburring. 

• Deburring service providers know that abrasiveness and the composition of media is another important aspect in the selection for tumble deburring media to have the desired outcome. 

• Steel media- This can be used to deburr other steel parts and has a good life span when compared to other media types.  
• Organic materials like walnuts, rice and corn cob granules can be used to polish and give parts a polished surface. They can also be used to dry parts and are less costly than media such as steel and ceramics. 
• Deburring metal parts made from titanium and steel with ceramics media is a good choice. Ceramics have a high density and with porcelain, can grind and polish hard metal alloys. The efficiency, however, will diminish as the ceramic material wears down and breaks into smaller pieces during prolonged use and must be replaced.  
• For softer alloys like zinc, brass, and aluminum, plastic media is often a preferred choice. It comes in categories of low density that is best used to remove small burrs and flash and general uses. High density type is good for use on ferrous and non-ferrous alloys. High performance media was developed for application on ferrous metals resulting in a high-quality surface finish that has an impact resistance of plastic. 

So many choices! Deburring media not only comes in varying sizes, shapes and abrasiveness, but also in choices of density and hardness to give longer cycle times, durability, and a desired finish. The choice is best made by communication with a deburring service on what kind of plastic or metal deburring system will result in the preferred finished part.