Very stable molecular wires made of zinc (II) octaethylporphyrin (ZnOEP) linked by 4,4’-bipyridine (4,4’-BP) were fabricated on HOPG. These molecular wires were prepared step-by-step, at the tetradecane/HOPG interface, being the deposition of each monolayer characterised by scanning tunnelling microscopy (STM) and scanning tunnelling spectroscopy (STS). Current-sensing AFM (CSAFM) was also used to assess their electrical properties. Under these conditions, molecular wires with up to 5 monolayers: ZnOEP/ 4,4’-BP / ZnOEP/ 4,4’-BP / ZnOEP were prepared, being each monolayer characterised with respect to molecular organization and electrical properties. The method was extended to longer molecular wires in order to study the dependence of the conductance on their length by using CSAFM measurements.