My favorite quote from the first article: "The varnish I used is intended for oven-drying at 140 to 150 degrees Celsius. I don't have an oven large enough to fit this coil, so I heated it by applying roughly 20A of direct current to the high voltage winding. I monitored the temperature by measuring the resistance change of the wire."

The solution belies a very deep understanding of the principles involved. Both the heating and the thermal regulation were improvised.