An apparatus, transfer cask, system, and method for defueling a nuclear reactor and transferring spent nuclear fuel from a spent nuclear fuel pool to a storage cask for long terms storage. In this approach, recanalizing the CTO is achieved using a combined antegrade and retrograde approach. Some embodiments may comprise defining protected memory. The fixture applies adequate force to each arm sufficient to hold a specimen in position between the anvil assemblies and establish a good abutting electrical contact between the specimen and each assembly but without exerting enough force to deform the specimen as it is being heated.