While swapping chuck jaws I realized I didn’t have to pile them on a shop rag atop the lathe headstock, no matter how neatly cut those rags might be:

It’s three layers of MDF cut to hold all six jaws from the 4 inch 3 jaw chuck, stuck together with wood glue.
You really need only four sockets: one empty for the jaw you just removed, then work your way around the chuck. But, hey, MDF is cheap and I usually remove all three at once anyway.
When it starts walking away, it’ll sprout silicone feet.
The LightBurn SVG layout as a GitHub Gist:
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That was easy!