Good vibes and strange vibes

In history many inventions were made by mere fortune. New scientific findings, products and technical expertise were often created by fortunate coincidences, sometimes even accidents. Teflon for example was invented or discovered accidentally in 1938 by Roy Plunkett. Other new insights, interestingly in the field of medicine, chemistry or industrial processing had been achieved by strong human curiosity and intense testing. Seldom theoretical and methodical frameworks delivered answers on how to process something, when a lot of parameters in a very complex system are influencing the result.

Sometimes a certain necessity is the origin of the invention, sometimes the invention creates a need afterward. For example the phonograph was definitely not needed by anyone before its invention by Edison. The invention itself created the need after a while. An invention creates new things or makes existing things better and it is an exploratory process with an uncertain or unknown result.

In the field of mass finishing products and processes the last decades have seen a constant flow of inventions. On the side of the products – the machines – there have been few really new concepts or sketches of totally new machines, as the main basic principles have not changed: vibration and centrifugal force. Nevertheless the existing concepts have been steadily improved, mainly due to a permanent market pressure for new, safer and better treatment processes on the surface finishing machines, which also always have an influence on the construction of the related machines.

But especially the processes running on these machines had been the target of intense testing and empiric research. Today every supplier of surface finishing machines has his own trial department, where customer products can be tested on standard machines. But new process findings do not arise solely from these Research and Development Departments of machine manufacturers. Very often customers of very different branches are testing treatments on their machines by themselves. These trial and error mechanisms applied by many people have led to a broad variety of processes, which can be run on classical surface finishing machines today.

So the functional bandwidth of a simple surface finishing machine is astonishing, especially if you consider the original construction purpose. Many people today do not know that these machines can do far more than simply deburring, edge-braking, polishing and other kinds of classical slide grinding. Of course these are the main treatments and that will not change in future. Nevertheless the other abilities of these machines include, for example:

• oil removal
• degreasing / greasing
• purification
• separation
• descaling
• conservation
• coating / impregnation
• coloration
• paint removal

These are only some typical examples for processes which round tub vibrators can support. Some of them, like oil removal, degreasing and purification, are very well known by users of slide grinding machines. But the possibility to conserve parts, to coat or grease them and to color certain materials surely sounds strange at first. As these processes are at the borderline of the original construction purpose, these treatments are sometimes not easy to handle and work only under certain conditions and with specific materials.

Coloration for example works well with absorbent material, especially with wood. Here this treatment becomes interesting when a workpiece should be painted with no chemicals and harmless color and no classical enamel varnish.

The conservation of material is often made with oil-impregnated corn cobs in a modified round tub drier. Oil removal, degreasing and cleaning can be done in nearly every kind of surface finishing installation. The right media and compound is the most important parameter for a successful treatment in this case.

Another very special and interesting application is a kind of polishing of tiny reflective glass spheres by piece against piece treatment. These spheres are used in white road paintings on German roads. These very small glass spheres with a diameter of below 0.2 mm provide the reflective property of the white color on the road. To generate a very good reflective capability, the glass surface has to be polished to great clearness. This is achieved by a piece-to-piece treatment with special polish compounds and much water in a round tub vibrator. Similar treatments can be found to handle precision glass balls for ball bearings and for dosing pump valves, closing balls for ink cartridges and other glass balls for usage in optics, aerospace and medical engineering.

Before one can say anything about the effectiveness of such treatments, even very skilled process engineers can only assume which process combination will be most promising. Authoritative results are only delivered by solid testing and trial documentation and a good portion of innovative thinking. So often a process invention is the basis for many special surface finishing treatments, or should we better call it a surface change treatment?

The process itself is determined by the kind of machine, machine adjustments, the quantity of parts in that machine, the kind of abrasive media, the water quantity and several other components. Sometimes a process consists of a sequence of two or more totally different sub-processes.

The possibilities are infinite. Every day companies are facing new challenges, new materials and new process questions. So in the future there will be much space for improvements and new process inventions on already-existing surface finishing machines. Sometimes these "innovative vibrations" will not only lead to good, but to fantastic new results.

Good Vibrations
by Mathieu Geuting
Spaleck Oberflächentechnik GmbH & Co. KG, Germany

Tel. +49.2871.9500.14
Fax +49.2871.9500.95
E-mail: m.geuting@spaleck.biz