Abstract: A metal disintegrating electrode for forming a hole in a metal workpiece such as a pipe by a thermo-fracture process without creating large chips or particles that otherwise would contaminate the inside of the pipe. The electrode comprises an elongated tubular sheath filled with a cluster of tubes or a cluster of tubes and rods which cause the metal of the pipe to disintegrate into small particles. The tubes also conduct a flow of coolant against the pipe and along the outside of the tubular sheath in order to promote the thermo-fracture process and to keep the electrode from sticking to the pipe.