I am making an Oscillating spindle sander. One of the main advantages of oscillating a spindle sander is to reduce sanding scratches. Most OSS's you buy use a constant velocity up and down motion, like a triangle wave. If you move the OSS spindle up and down using a gearmotor and a pitman arm, you will get a sine wave motion, where the velocity is faster in the middle of the strokes and slows down to zero velocity at the ends of the strokes. But I wonder how much difference it really makes if you use the sine wave motion Sine wave motion is much simpler to make on a DIY made OSS.
sine.jpg
triangle.jpg
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