Working with text Text carving and CNC milling are a natural match. This ring is just a rather simple exercise playing with a whimsical font. Much more sophistication is possible, the major limitation is the size of the milling bit in relation to the overall letter size. I've found that the lower legible size limit to be around 1-2mm for simple letters, with detailed complex fonts needing to be larger.
Rhino model Rhino3D has a number of tools which are quite useful for manipulating TrueType fonts. From extracting the basic vector geometry, flowing , bending, twisting and scaling these curves, to reconstructing as 3D objects. For this example I started with the basic curves from HAND-ME-.ttf Since fonts are designed for ink and screen some changes are necessary to get pleasing results when milled. Both positive and negative spaces must take into account the cutting tool geometry and wax properties. The change in medium results in a related but new font. I usually use offsets and control point manipulation to modify the curves. Then extrusion into 3D solids and boolean operations to construct a model. For milling with a rotary axis substituting for a linear axis the model should be flat, wrapping into a ring shape is a useful visualization technique.

Copyright © Jeff Demand 2003