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world gathers for metal finishing
Q&As since 1989


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Drag Finishing?

Do you have any information on Drag Finishing, such as how it has been applied and what companies are using it? What products are be finished by drag finishing, and what companies are manufacturing equipment for drag finishing?

Gerry Austin
Washington State University
1998

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From a distance, drag finishing looks sort of like vibratory finishing. But, instead of shaking the bowl of media, and fluidizing it, the part is dragged through the media. The part makes a circuit like the earth, i.e., it follows a planetary orbit through the bowl and also rotates around its axis. Drag finishing is used for all kinds of polishing operations, but each piece part has to be fixtured, so it's more appropriate for large items than tiny ones.

Walther Corporation in Heber Springs, AR manufactures these units. They have a unit installed for prototyping in their factory there; I visited them and saw some of their development work, and admit that I was impressed.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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In reply to your inquiry on Drag Finishing. Yes, Drag Finising is a process where a part(s) are fixtured to an individual fixture which are then "dragged" through a stationary bed of media at a high rate of speed (sometimes generating up to 25RPMs on a turret which may be 8' in diameter. Drag Finishing is generally up to 40 times faster finishing than the more conventional vibratory finishing, yet is more geared toward providing finishes to parts with extreme contours and geometries, parts previously hand polished, and parts which take extremely long periods of time to finish. Dynastar Finishing of Fond du Lac, WI is the only job shop facility in the World providing job shop services exclusively. This company has five drag finishers providing finishing to a wide range of parts.

Tim Dyer
Advanced Finishing Tech. - Grand Rapids, Michigan, USA
2000