After a few test drives, this one may be worth refining into something I would keep around.
Some old melamine, an oak runner and some parts out of the coffee can. The two screwheads act as a stop, the tongue keeps it tight to the table and my belly keeps it snug.
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Drill a hole to fit the adjustable pivot pin (an old screw).
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The slide allows me to . . . well, slide into the initial cut.
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Give it a spin and there you are.
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