The mechanical data (loads, displacements) recorded during double torsion experiments on samples of 6 shale materials and a sandstone. These experiments were conducted on the I12 beamline, Diamond Light Source, Harwell as part of beamtimes EE13824-1 and EE13824-2 between 26/02/17 and 03/03/17. The data were collected using the standard double-torsion technique, with a load cell behind the actuator recording applied force. The method and results are described in detail by Chandler et al, (2018,submitted) "Correlative optical and X-ray imaging of strain evolution during Double Torsion Fracture Toughness measurements in shale" The data was collected with the aim of correlating local deformation around a progressing fracture (through X-Ray and optical imaging) with recorded mechanical data from the loading system. The data was collected by M. Chandler, A-L Fauchille, J. Mecklenburgh, H. K. Kim and L. Ma, and was processed by M. Chandler and R. Rizzo. The complete dataset is present.