What is mass finishing?
Mass finishing simply put is surface treatment in batches. These abrasive processes include improvement of surface texture, de-burring, de-scaling, edge-break, mirror/micro finishing and decreasing radius. The major purposes of mass finishing is to lower labor costs and to ensure a consistent finish. These finishing processes are indispensable for parts to perform their required functions but are inconsistent and costly when done by hand. Mass finishing lowers costs and raises quality consistencies.
What does ‘barrel’ mean?
Barrel finishing is derived from an ancient practice used to polish raw gem stones. A rotary barrel is the oldest type of its kind and the shape of the barrel is similar to the one ancient people used to polish stones. Generally, in Mass Finishing 'barrel' refers to the container in which the process is completed. There are many types of 'barrels' in mass finishing.
What is a ‘compound’ ?
Literally compound just means a mixture but this word carries different meanings in different industries. In the finishing industry, it mainly means a detergent, keeping media and parts from becoming contaminated thus losing its effectiveness of water softening, shock absorbing and lubrication.
How should compound be used?
A compound is a concentrated cleaning agent and is used in a form of a solvent by diluting it into water, some are in a liquid form and some are powers. Basically the concentration of compound solution is 1 - 2 % but varies depending on the type of machine, the compound used and the process time needed.
Why is water used in process finishing?
In a finishing process, water and compounds are used for similar purposes. The main role is to keep the parts and media clean by suspending soils and not allowing them to be re-deposited. By doing so, this provides the desired part finish while keeping media from becoming contaminated and losing its effectiveness of water softening, shock absorbing and lubrication. Often an flow through of a compound/water solutions is necessary to maintain the optimal finishing condition. Dry barrel finishing process with no water required is also available.
How much water should be charged?
It is quite a difficult question to answer, because the water charging volume varies depending on the type of machine and the process target. Generally speaking, the water volume in a barrel is 40 - 50 % of the total barrel capacity. As for a Vibratory Finishing Machine, only 3 - 5 % of the capacity should be charged. Water performs an important role together with the compound used (see above).
What is abrasive media ?
Most abrasive media used for finishing is artificially developed. Therefore, there are standards in abrasive media in terms of ingredients, manufacturing processes, shape and dimensions. A suitable type of abrasive media will be selected depending on the finishing purposes, raw materials of the work pieces and the type of finishing machine used.
How many types of abrasive media are there?
There is many criteria to categorize types of abrasive media including aggressiveness, shape and size to name a few. When including all categories, there are several hundred types of abrasive media each with a specific advantage. Often an certain media or process will finish parts to the required specifications but is not the optimal process for the parts when considering efficiency and cost reduction.
How long should abrasive media be used?
Abrasive media can be used, if there are no restrictions, even as they wear smaller in size. However, in practical cases, due to holes and grooves on work pieces, worn media may lodge therefore classification of media sizes is often necessary. In addition, parts have to be separated from abrasive media after finishing process; therefore, each process has different types of restrictions.
What is the appropriate ratio of mixing abrasive media and work pieces?
In terms of polishing efficiency, work pieces and abrasive media should be mixed in a ratio of 1 to 4. However, work pieces made of soft metals such as aluminum are easy to damage by part-on-part impingement. In such a case, the volume of abrasive media should be increased. The important factors are the size, weight and hardness of work pieces.
Home 
About US 
Media Stones 
