The aim of the present work is to design a simple torsion fixture for bonded joints that is adaptable to conventional testing machines and at the same time gives reliable results. This is achieved by transforming a traction or compression movement of a conventional machine to a torsion one on the bonded joints. In the present study, a full description of the mechanism of transferring a compression/traction movement to a pure torsion is explained, and the validation approach is outlined. Finally, experiments on bonded joints are performed and compared to step lap shear test. The results showed that the proposed torsion apparatus is very promising in measuring the strength of bonded joints.