From render to 3D production files: the spec gates before export
mulapis Research
A 3D production file is a three-dimensional model that can be handed directly to casting and fabrication. It differs from a render in its goal: the render's job is to show the design accurately; the production file's job is to make it buildable. At mulapis, confirmed designs export directly as production files with no manual remodeling, once they clear the specification gates below.
Wall thickness and minimum feature size
Casting has physical floors: walls below the minimum starve the metal flow, and details below the minimum never take shape. The band, the prongs and the milgrain beading each carry their own minimum size, and every region of geometry in the file must clear its floor. This is a local physical constraint checked point by point, not a judgment of appearance.
Every stone needs a seat
In a render, a gemstone can simply rest on metal; in a production file, it must be set in metal. Every stone maps to a seat with support underneath, prongs or channels to hold it, and a hole drilled to the stone's actual diameter and depth. A pavé design with dozens of side stones means dozens of seats, each of which must individually work.
Ring size and room to resize
Ring sizes map to precise inner diameters (size 14 measures 17.3 mm). The production file must match this measurement while leaving enough shank to resize up or down without disturbing stone seats.
Gold weight comes from volume
A production file is a closed solid, so its volume is determinate; multiply by the alloy's density and you have the gold weight. Once the volume exists, material cost follows immediately. Gold weight appears on the spec because volume and metal density determine it directly, with no guesswork.
Integrity of the file itself
A model delivered to production must be a watertight mesh: no open faces, no overlapping surfaces, correct units and scale. File defects do not show in renders, yet they halt fabrication downstream. They are easy to overlook and expensive to fix late.