If you want a machine with the capacity for much finer work than a normal EDM, and which can be used to burn reverse artistic images into tool steel for molds, or the like, then you need a Pulse EDM, in which the spark is controlled by a timer and power Mosfets.
Normally only available as very expensive complete machines, here genius Ben Fleming describes how you can make your own Pulse EDM at reasonable cost.
You will have to have some electronics knowledge (or acquire it), as well as mechanical engineering ability, but this is a great project. 127 page large format paperback, full of drawings, schematics and B&W photographs.
8 1/2 x 11 format, 4 color cover
155 photos B/W