The present invention relates to a rotor shaft and rotor body assembly in an x-ray device, and it method of manufacture, that resists the formation of cracks in the braze joint due to the elimination of horizontal shear planes therein. The inventive structure also comprises an enlarged proximal end of the rotor shaft and an inventive assembly method that prevents the rotor shaft from de-coupling from the rotor body should the braze material entirely fail during field use.