March, 2003 - NCWT Meeting
Jim Bohmer Demo - Dynamic Spheres
Click here for a printable version Jim's article.
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Below are some pictures from the Demo. Notice that the headstock of the lathe is on the right from the turner's position. The pictures are not backward. Jim is left handed and has turned the lathe around. Keep this in mind as you view the pictures below. |
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Jim discusses the thoughts and origins of his "Dynamic Spheres" |
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Jim describes selection of wood and turning dowels to make plugs to fit in 1 3/8" holes. The overall blank is 4"X4"X4 1/4" |
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The blank is mounted between centers and turned to a cylinder with a roughing gouge. |
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Jim begins to round the blank into a sphere. Note the display on the television screen that gives the large attendance closeups of Jim's turning. |
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Jim demonstrates how he judges roundness with his cup center. He holds the center with the edge of the center on the edge of he sphere to judge roundness. |
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With the first axis turned, he rotates the "sphere" and places it between cup centers to turn the second axis. The sphere is rotated again and turned to a nearly true sphere. Jim will claim that his spheres are not truly round, but from club member observations, they are very, very close!!! |
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Jim makes the race to insure that the spheres rotate freely in a track around the edge of the race. Spin away, a challenging and fun project. |
