one-includes-all conformal mesh: tetras and triangles
a conformal mesh for each part, fluid mesh (fluid is a part)
one part = one file, Tetra mesh + triangular surface mesh
each triangle separates two parts (imprint information)


Boolean operations (subtract) are performed according to the "last part wins" rule.

Left: 18 part disc brake assembly. Low level fluid tetras are removed.
Right: Imprint areas: Each area separates two parts. The part-fluid imprints are omitted.