Stone relief carving needs a shallow, inspectable map

Stone is heavy, brittle, and unforgiving. A deep relief with thin bridges and vertical walls can chip, break, or become impossible to undercut. A shallow relief with broad planes and gradual transitions is more likely to survive the tool and the material. The preview should be judged for those qualities, not just for likeness.

Choose a subject with a strong silhouette: a portrait, an architectural detail, a leaf, or a simple animal form. Fine hair, wire, and isolated small features are poor candidates because they require thin stone. If the subject depends on those details, a different material or a different process is a better fit.

The exported STL is a closed height-field slab, but it is not a toolpath. Stone carving requires a CAM strategy that accounts for the cutter, the spindle, the feed, the stepdown, the fixturing, and the dust or water management. The workbench gives you a shape to inspect; your CAM package and your experience decide how to remove the material.

Do not send the STL to a machine without checking the scale, the orientation, and the mounting. A stone blank is not a piece of foam; a wrong origin or a loose fixture can ruin the block and damage the tool. Test the setup on an offcut before the final stone.

A photo with a clear subject and a quiet background produces a cleaner relief. A busy scene with many overlapping objects produces a field of small transitions that stone cannot resolve. Crop to the form you want, remove distractions, and keep the border stable.

If the source is a portrait, inspect the eyes, nose, and mouth at the final size. Stone can hold a surprising amount of detail, but only if the tool can reach it and the material can support it. A softer, broader interpretation is often more durable than a literal copy.

Use the same stone, the same tool, and the same setup for the test. Carve a small area that includes the deepest cut, the finest detail, and the steepest slope. If the test chips or the tool chatters, change the design or the process before the final block. The free preview is a visual check; the offcut is the physical check.

Record the file, the stone, the tool, and the settings. Stone is expensive enough that a repeat job should not depend on memory. The workbench gives you a documented starting geometry; the carving record is yours.