Motor Rotation for Vibratory Finishing Machine

Question:

We bought a used round vibratory finishing machine and cannot find any indication of the proper motor rotation. Does it matter which way the motor rotates? Thank you, in advance, for your help. G.W.

Answer:

Yes, it does matter. With fully adjustable weights you can run the machine either way. As the weights rotate, the bottom weights should lead the top weights by 60–120 degrees. The media will travel around the bowl in the opposite direction. With internal separation, that travel has to be such that the media will climb toward the separation screen. Without internal separation, the direction is not critical. Once you establish the desired direction you are ready for some fine tuning. Lead angles below 90 degrees will cause the parts to roll more rapidly. This keeps the parts in the mass and also helps to prevent smaller parts from riding around the outside periphery. Angles above 90 degrees are used with heavier parts to keep them in the center of the mass, avoiding damage caused by heavy parts hitting the bottom of the bowl and impinging on media particles or on other parts. Higher angles also increase the travel speed around the bowl and are useful to help drive the media onto a separation screen.

You may also have the option of adding or removing weights to the top and bottom of the shaft. More weight on top will cause the mass to rotate around the machine in less time. This, along with a higher lead angle, is the variable used for getting parts up on an internal screen separator. However, this will also increase damage to parts as they impinge the center post. If you do not have an internal separator, you will get the best performance with fewer weights on top, and with a lead angle below 90 degrees.