The layout geometry is about finding isohedron inside the sphere.
An isohedron has 12 vertices and 20 faces
The true compass setting is a tiny bit bigger than the radius - about 1.05 x radius.
The radius works well on small spheres because it is within a 1/16” for a 2.5”sphere
1.25 is easy to find on the ruler 1.31 isn’t. Lets go to metric!!
The tapered holes are drilled at the 12 vertices of a regular isohedron
The small decorative holes are drilled in the centers of the 20 faces of the isohedron.
The reference below we need to find “a” the edge length 1.05=1/.951
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