Cutting the Swan Soundhole
The Swan soundhole is cut in with miniature routers and files. The shape is determined by a paper template.
Next, a Dremel Multi-Pro tool is used in a plunge router base to route the shape. The router bits are carbide "fish scale" cut miniatures, available from MicroMark, a supplier of miniature tools and supplies. The shape is cut progressively, starting with a 1/8" tool and proceeding by 1/32" increments of diameter down to 1/32" for the finest detail. Some chipping will be inevitable, but can be minimized by making the final cut with the 1/32" tool in two passes: first cutting only halfway down, and then a second pass cutting clear through the top and its brace.
Finally, the soundhole shapes are refined with miniature files and the X-acto knife. The most useful file shapes are the knife, half-round, and triangle. A tweezers is also handy for picking out the stray fiber. The edges are then finished off with a light scrubbing with a #400 grit manicurists nail shaping board.