Tumbling media are materials that are used in the finishing process. They are loaded with parts to be finished into finishing machines, with or without tumbling compounds. They help in cleaning, smoothing and deburring of parts. Tumbling media can be man made or natural. Man made media include plastic media, synthetic media and ceramic media which come in preformed shapes. Natural media include walnut shell media and corn cob media. Tumbling media are used in finishing machines like tumbling barrels, vibratory machines and centrifugal machines.
Plastic media are otherwise known as tumbling stones. They come in shapes like cones, pyramids and triangles and have varying abrasive properties. They create smooth but dull finishes on surfaces and because of their light weight are suited for use on parts that might get damaged easily. They are safe on threaded parts and can be used on parts as a pre cursor to anodizing. The cone shaped plastic media act well on parts with holes and triangle shape acts well on edges and flat surfaces. Multiple shapes can be used on parts with complex designs.
Ceramic tumbling media are made of silica, minerals and abrasives mixed in different proportions and processed at high temperatures to produce hardened shapes. They are good for aggressive finishing needs and work well with hard metal parts. They suit usage with heavy loads that cannot be handled by plastics; they also come in smaller sizes and hence are suited for smaller parts. Synthetic tumbling media also come in different shapes; they weigh lesser compared to ceramic media. They are cost effective and are good to provide ultra smooth finishes. Compared to plastic media, they take more wear and tear and residue left from processing is lesser. They are ideal for use in high energy machines like centrifugal barrels.
Tumbling compounds are chemicals used to increase the effectiveness of media by ensuring that glaze is not formed on the parts during the finishing process. They act as abrasive agents and help in maintaining a nice color to the metal parts. They impart anti rust and anti corrosion properties to the parts when the right agents are added to them; they are effective cleaning agents and help in deburring by suspending debris and preventing them from getting re-deposited on the parts. The compounds are either alkaline or acidic in nature depending on the media they are used with.
The flow rate of the tumbling compounds should be matched with the volume of media being used for a good finish. Tumbling compounds are known to help in degreasing, descaling and removing grime. They help in lubrication of parts to protect them. They help in grinding, polishing and brightening of surfaces. They help to finish delicate parts by providing a cushioning effect and preventing damage to the parts. Acidic tumbling compounds enhance cutting speeds and bleaching efficiency. When used in proper combination with finishing media, tumbling compounds help to reduce cycle times substantially. To learn about the advantages of tumbling media and tumbling compounds, go to http://gravcollc.com/
Posted 1 year, 3 months ago at 7:42 pm. Add a comment
‘Media’ is the terminology used to define a material that is used to modify or alter the appearance of a part. It generally refers to an abrasive, but it could refer to any material that can abrade, clean, polish or separate parts. Tumbling media is used in general purpose metal polishing, deburring – both light and heavy, fast and extra fast and aggressive metal removal, fast, heavy cutting, jewellery polishing, burnishing etc. There are many types of tumbling media like ceramic performed shapes, plastic performed shapes, synthetic performed shapes, precision ceramic preformed shapes, carbon steel, stainless steel, hardwood, aluminium oxide, corn cob, silicon carbide grit and walnut shells are some of them.
A finishing media company has to give high quality products at reasonable prices to their clients. A fully equipped laboratory stocked with finishing machines where new processes are developed to meet even the toughest application will make them effective innovators. Plastic media is normally used for pre painted or pre plated finishes, polishing and in cutting fast and heavy duty. Plastic media are ideal for soft metals like brass and aluminium and stringy materials. It is useful for providing a smooth but dull finish. These media are long lasting and are built to cut fast and provide a fine finish. With a vast experience, a company can provide customized solutions to their clients. Ceramic tumbling media come in different shapes, sizes and composition. Ceramic media are used for fast deburring and tough metal removal. It is mainly used in cutting hard metals. When media of smaller dimensions are needed, ceramic media offers the best options. It is better than plastic media in supporting very heavy metal parts.
Dry finishing media of smaller dimensions are used to polish and finish smaller surfaces like jewellery. For this, cob and walnut shells that are treated are used and a finishing paste is also typically used for this. Very delicate surfaces of any size can also be finished using corn cob media. Corn cob is bio degradable and it is a tumbling grit. It can be applied as tumbling and vibratory media and can dry parts by absorbing oil and dirt, without scratching the parts’ surfaces. These products can be used to finish even very small and delicate surfaces effectively. Their product formulas can achieve 1 Ra finish and are made to handle even finishes of a delicate nature for decorative requirements.
There is a wide range of tumbling compounds to satisfy different client needs. Dry compounds, liquid compounds, burnishing compounds, cleaning compounds and deburring compounds are some of the available finishing tumbling compounds. There are compounds for standard deburring applications, burnishing of steel, part on part and applications in washing different parts. Walnut shells are treated and prepared by grinding them into different grit sizes. They are used in cleaning as well as polishing of surfaces. It is recommended as tumble media for polishing metals like aluminium, brass and bronze. They are soft abrasives but highly durable and angular. To learn more, go to http://gravcollc.com/
Posted 1 year, 3 months ago at 9:12 pm. Add a comment
Finishing media and finishing compounds can be defined as material that are used to remove sharp edges and burrs from parts to make them smooth and provide a good finish and polish effect. There are vibrators, tumblers and spinning machines among others that are used to produce the finish. The finishing media and compounds are used in these machines for varying periods of time to give the desired finish or polish.
Corn cob media come under the dry finishing media type. It is treated corn cob that is powdered to different dimensions depending on the finish requirements. They can be used to achieve very fine finishes in the 1 Ra range and meet any requirements for a decorative finish. Corn cob media is environment friendly as it is made from the hardened cob ring and is organic in nature. It has the advantage of being capable of use as tumbling and vibratory media and can absorb oils, grease and dirt. It can be used to dry parts while keeping their surface safe. Corn cob media also finds use as a burnishing grit for soft metals like brass and bronze. The weight and type of the part to be finished determine the size of the corn grit in the corn cob media.
The corn cob media are re-usable and long lasting as they do not break down easily. They are bio degradable and organic in nature; they can be burned. They are very clean and pose no environmental threats. They can be used effectively on plastics as well as metal surfaces for giving a good finish. They are capable of absorbing water and oils and are effective cleaners. They can be used even on parts with micro finishes as the corn cob media does not harm the surfaces. They are very cost effective too.
Vibratory systems impart a cutting and finishing action by vibrating the processing tub at certain speeds which causes the media or vibratory compounds to scrub against the parts. The scrubbing action in turn removes or cuts sharp edges and provides a smooth finish on the parts. The vibratory compounds can be used in places where precise finishing is required. For instance, to remove excess material embedded in the recesses of a bore, they can be used effectively. They can also be used on large surfaces without worrying about the surface safety as they are gentle even on delicate parts. By controlling the speed of the vibratory system, it can be used on smaller or larger surfaces. BC-300X is one of the wet vibratory compounds and is used for burnishing of parts. It is acidic in nature and can be used on all metals. It is very effective with steel media. It is super effective in cleaning and imparts a corrosion inhibitor for all metals. BC-320 is a wet burnishing compound that works well in vibratory machines. It is specifically for use on aluminium metal and produces a very bright finish. For more information on finishing media, go to http://gravcollc.com/
Posted 1 year, 3 months ago at 8:00 pm. Add a comment

David Scheetz is principal owner and CEO and Robert Summey is Sales manager. These two together bring over fifty years of metal finishing experience to Grav Co LLC.
Grav Co LLC manufactures the finest mass finishing equipment and supplies in the marketplace. We build Torex vibratory finishing machines, deburring machines, Grav-i-Flo disc finishing, high speed and low speed barrel finishing, tumbling barrels, centrifugal barrel machines and spin finishing equipment in our Sturgis, Michigan plant. We also manufacture vibratory finishing media, corn cob media, plastic deburring media, walnut shell media, and various liquid and tumbling compounds, and have a very good line of ceramic finishing media.
The trade name Grav-i-Flo has been synonymous with quality finishing equipment and supplies for over sixty years. We are able to provide you a quote on standard equipment, and supplies in one day or less. We ship most supply orders in one to two days. We are a world class supplier of finishing equipment and supplies.
New Products
A new product line currently on the drawing board is standard parts washers. We are building a cellular style belt and rotary drum washers. If you have a parts washer project currently that you think a simple belt or drum washer will suffice, we build a very good washer at a very competitive price. Try us, I think you will like the products and our team. Let us help you resolve your finishing needs.
Posted 1 year, 3 months ago at 5:45 pm. Add a comment