Assembly injection molding is a well established process for the manufacturing of assemblies using similar (compatible) or dissimilar (incompatible) materials to create movable or fixed joints. Usually, a first component is injection-molded and subsequently overmolded with a second shot. Within the joining of two polymers the quality of the resulting interface is dominantly affected by the thermal history at the contact area between the two components. With the scale down to micro assemblies the manufacturing of material bonds becomes more challenging. In this study the mechanical properties of assembly injection molded tensile rods with a diameter of 0.6 mm were investigated and compared to weld lines and the reference material properties varying the process conditions.