This simple fixture is easy to make. I would estimate that it took me about 5 hours to make. Some fixturing for router base is required to cut the arch shapes. I'm hoping to start turning some bowls very soon.
I made this fixture to go on my Shopsmith Mark V. The overall outside diameter is 16 ". I used two pieces of 3/4 " thick oak plywood. On the back side I attached my face plate. This attaches to the motor spindle. The black round items you see are a #2 Rubber stopper with a 1/4-20 x 3" long bolt with washers.
The basic function of this fixture is to place your finger in the round 3/4" dia hole and rotate the outer disc either towards you or away from you. Because of the arch shapes you see the rubber stoppers will follow the arch while keeping a continuous diameter shape required to fit a bowl. As you place the bowl against the outer disc you rotate the outer disc until you are fitting tight against the bowl. While holding in place with one hand, reach behind and tighten the wing nuts behind the stationary disc. To better see how this functions view the video link that I show above.
If you have any questions about this project feel free to contact me.
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