Abstract: A riveting device for the assemblage of two or more sheet metal sections (A, B) of a structure comprising a working unit (14) operable on one side of the sections (A, B) to be assembled and a clamping and bucking unit (26) operable one the opposite side of the sections. Both units (14, 26) comprise clamping means (16 and 31, 62, 72) respectively, by which the sections (A, B) are clamped together during the entire working cycle in each rivet position, i.e. during hole making, seal compound application, rivet insertion and rivet upsetting. The clamping means of the bucking unit (26) comprises a head (62; 90), one or more low inertia contact elements (72; 94) and a resilient impact absorbing means (66; 101, 102) provided between the contact element or elements (72; 94) and the head (62; 90).