Tumbling-Media

Mass Finishing Renders High Quality Parts

Parts that are manufactured usually need removing of jagged edges, cleaning and polishing before they are fit to satisfy their functionality (the function for which they are being built). This is achieved by means of a process called finishing. Mass finishing is several parts being finished all together. It is typically carried out in finishing machines or systems like tumbling machines, vibratory machines, blasters, centrifugal machines etc. Parts are fed into these machines along with finishing media, finishing compounds and water. The parts and the finishing media scrub against each other, with the compounds aiding in removing the debris and keeping it from re-depositing on the parts. Due to this scrubbing action, mass finishing takes place - edges are smoothed, surfaces get polished, nooks get cleaned and parts get broken from runners.

Finishing media are materials that aid in the mass finishing process. There are many types of media like synthetic pre formed plastic media, ceramic media and natural media like corn cob and walnut shell media. Finishing compounds could be dry or wet and depending on the action required, their composition varies. This determines their abrasive action, alkalinity etc. Mass finishing process can take place as a batch process, as a series of steps or as continuous process. In a batch process, parts are loaded as a batch and after finishing, the batch is unloaded. The next batch now goes in and so on. In the step by step process, the parts are taken through a sequence of processes, one by one. After every step, the parts will have some degree of finishing done on them and after the final step, they will be fully ready. In a continuous process, the loading and unloading of parts happens continuously, while the finishing process is carried out.

Walnut shell media are made from treated and crushed walnuts. As they are natural, they are bio degradable and safe for the environment. They are dry finishing media whose grain size is determined by the weight and composition of the parts being finished. They are very good cleaners too apart from being good polishers. They are suited for use with tumble machines and useful in finishing of parts made from soft metals like brass, aluminium and bronze. Mixed with paints, they act as anti skid agents and are typically used in paints used around swimming pools and pathways. Oil well drilling is another area where they are used, to prevent the oil from stagnating.

Walnut shells have the properties of hardness and fibre. They are also naturally angular and multi faceted, which makes the walnut shell media ideal for deburring. They last long and can be reused many times over. Used in tumbling and in some vibrating systems, they help to reduce cycle times. They can be used on delicate surfaces because they do not have a rough abrasive action. So, they do not damage micro finishes. There are companies who have been in the finishing business for a long time; they can find finishing solutions for any needs. To learn more visit http://gravcollc.com/

Go For A Smooth Finish With Finishing Compounds

Finishing is a term used to define the process of cleaning, polishing, deburring, coloring, separating and smoothing of parts or components, generally metals. Finishing compounds are compounds used in the process of finishing - they are defined as substances or materials that are used to give surface properties like softness, smoothness, flexibility, resistance to fire, resistance to corrosion, resistance to rusting and so on - to metal parts, wood, textile, leather etc. It is possible to impart a high quality to a finished product with finishing compounds so that the product comes out with the correct functionality, fit and aesthetics.

Mass finishing compounds are used to finish several parts together using machines like tumbling barrels or vibratory systems. The compounds are used to aid in deburring, descaling, polishing of ferrous and non ferrous materials etc. The typical mass finishing process involves putting the parts together with finishing media, water and finishing compounds into a barrel or vibratory machine and allowing them to vibrate or tumble together. As a result, the parts rub against each other or with the finishing media; the rough edges are smoothed out, debris and deposits are cleaned out and specific surface properties are imparted to the parts.

The finishing compounds can be used in closed loop and open loop finishing processes, which involves automatic or manual feeding of finishing media and compounds respectively. There are compounds that are made for wet use and those made for dry use. Compounds are also available for specific use with tumbling systems and those that work well with vibratory systems. There are some special properties given to the finishing compounds when they are manufactured. For example, deburring compounds are made to keep the deburring debris suspended during the finishing process to ensure that there is no re depositing. This way the surfaces are continuously kept ready to accept the abrasive action. Descaling compounds have properties needed to remove scales and assist the finishing media in descaling. Compounds used for polishing are made to provide conditioning to water, detergency, impart rinseability and brightening plus suspension properties to make sure that the debris is kept at bay.

Finishing media are used in the finishing process to clean, polish and deburr. Corn cob media comes under the head of dry finishing media. It is made from treating and powdering of corn cobs to provide abrasive action on parts being finished. As they are made from natural products, corn cob media is bio degradable and environment friendly. It is long lasting and reusable; it is also cost effective. It can be used in both vibratory and tumbling systems. The grit size of the corn cob media is determined by the finishing requirement – it varies depending on whether the finishing process needs to be gentle or rough, the nature of the surface being deburred etc. The corn cob media has very good absorbing properties and can absorb both water and oily substances with ease; proves very effective in degreasing and cleaning parts. To gain further insights into finishing products, log on to http://gravcollc.com/

Tumbling Barrels Provide The Needed Finish

Deburring machines are better known as finishing machines. Their purpose is to finish parts – by facilitating polishing, cleaning, separating and deburring actions. There are two important types of mass finishing deburring machines – tumbling barrel machines and the vibratory machines. In all the deburring machines, the parts are loaded along with finishing deburring media, finishing compounds and/ or water. Deburring media include ceramic media and plastic media that are man made and corn cob media and walnut shell media that are natural. Finishing compounds come as wet or dry compounds. Their composition varies depending on the abrasive action that is needed, inhibition action (like anti corrosion, anti rust) and the suspension properties needed. The compounds help to suspend the debris that comes out during the finishing process in deburring machines. This prevents the debris from getting deposited or lodged back into the parts.

Vibratory deburring machines involve a tub or a bowl that is shaken at high speeds which causes the parts and the finishing media to scrape against each other in a filing kind of motion. In a vibratory machine, the sliding action happens on all of the load with a single vibration; there fore cycle times are very less compared to tumbling barrels. They are high speed, short stroke machines and hence are good for delicate parts as well as large surfaces. They are very useful as separators of parts. The loading and unloading of vibratory machines is very simple. There are also other types of deburring machines like centrifugal machines, blasting machines and spinning machines that are used in special cases. In the blasting deburring machines, some media are blasted on to parts to deburr them.

In a tumbling machine, tumbling barrels are present to hold the parts and the finishing media and compounds. They are available as floor (large) and bench (small) models. The parts and the finishing media are lifted from the barrel’s corners by the movement of the machine and they bump and slide against each other. The media that is used in barrel tumbling depends on the roughness of the finishing that is required, the nature of the parts being tumbled and whether polishing or deburring is the prime requirement.

In barrel tumbling, parts can be used without using any media too in special cases. Usually, barrel tumbling is used for wet processing but in some cases where there is a need, dry finishing can also be done using them. Wet barrel finishing is intended for processing metals. They can be used for removing burrs, polishing and improving surface appearance. A dry barrel system gives a finish that is smoother and more uniform than a wet finishing barrel. In factories where there is not much water, dry barrelling is the ideal option. Tumbling barrels are ideal for heavy loads; they function optimally when they are 50 % loaded. Screen doors can be added to barrels for use in separating parts. For more details on the different kinds of deburring machines available from finishing industry experts, go to http://gravcollc.com/

Finishing Parts Using Vibratory Systems

Mass finishing can be best described as processes in which a number of parts are simultaneously finished. The finishing involves burnishing, deburring, cleaning, removing rust, polishing etc of the parts. The two main types of mass finishing are tumble or barrel finishing and vibratory finishing. In both types, a cyclical action is used to create a grinding action between the various surfaces. Some times, the parts are finished by rubbing against each other. But more often than not, some media is used to achieve finishing. The finishing process can be wet or dry. For a wet finishing, a liquid is used as a cleaner or abrasive. For a dry process plastic, ceramic or dry compounds are used as media. Finishing times vary with the composition of parts. For non ferrous materials, it could be just 10 minutes and for hardened steel, it could take more than 2 hours.

Mass finishing is an art while being a science because the processes involve random action. The mass finishing process could be organized as batch processes, continuous processes or sequential processes. In batch process, a batch of parts are input, worked on and pulled out; the next batch is now input and so on. In a continuous process, the parts are fed and pulled out continuously. In a sequential process, the parts are put through a sequence of processes one after the other. Normally, after every sequence, the part is in a better finished state.

Media are used in mass finishing to accomplish one of four things - cut, luster, parts separation and scrubbing of surfaces. The media could be aluminium media, preformed ceramic media, preformed resin bonded media, preformed shapes in steel, synthetic random shaped media, natural media in random shapes like rocks, cob meal, walnut shells etc. Compounds are used in mass finishing to aid in deburring, cutting, burnishing and so on.

Vibratory finishing machines are used in the vibratory finishing process. The process involves using components like water, finishing media and finishing compounds. Vibratory finishing machines are designed to produce highly smooth surfaces and can act inside deep cavities like tubes. It can be used on varied parts - for delicate parts or large surfaces, which may not be possible in a tumbling process. Loading and unloading vibratory finishing machines is easy. They also have the advantage of lesser cycle times, better cleaning and better color maintenance. These machines are easier to maintain as compared to tumblers. They can mass finish more parts and have less wear on media. Automating or semi automating them is easier compared to tumblers.

Vibrators typically do not have speed control; however, a few of them do. The usual speed is 1700 vibrations per second; for lesser speeds, the parts may sink to the bottom making the finishing process less effective. Vibratory finishing machines work at optimum level when they are between 75% and 90% full. Three parts media to every part metal can be used for delicate parts. For more aggressive finishing, parts can be used without media. http://gravcollc.com/ will provide further details.

Manufacturer of Tumbling Media

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.