Instead of being made from one continuous piece of material, a coil includes multiple flat coil segments that are stacked together and electrically coupled in series. In many embodiments, the coil segments are U-shaped segments, and the segments are arranged so that each segment is rotated (e.g., by 270 degrees) with respect the segment it follows. The stacked coils may then be fastened together using, for example, bolts through the corners of the coil segments. The combined coil segments form a continuous coil.