Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4967195.
The previous print-in-place design was quite an ambitious 36 hour print, sensitive to clearances and elephant's foot. It was a lot to ask for an all or nothing chance at success. This version is designed to be printed in separate components and assembled. The aim is to produce a version suitable for SLA printing in separate pieces, though this one is still for FDM. Print at 0.2mm layer height (less important now, only really applies to the core or not at all for the alternate core).
Older video explaining mechanism Will put together an assembly video soon, but it's pretty self explanatory and reversible (see pictures). Some action shots.
Note: Parts are in assembled position, not the ideal printed layout. I would suggest flipping the "upper" shell over. For the dials, I prefer a small support disk by enabling support interface at 100% or just print internal side down. Following over-extrusion, "Z" seams are most likely to cause binding issues with moving parts. Random Z Seam Alignment may help.
As for finishing, it is designed for painting and sanding back to reveal detail. I'm thinking instead of paint I will try some kind of low shrinkage resin with pigment powder to fill the low spots. This should allow for a polished flat surface completely hiding any layer lines.