Flexible electronics is a rapid emerging trend in consumer-electronics with ever-increasing applications showing feasibility of functionality with flexibility. Aerosol Jet printing technology has gained rapid acceptance for additive printing owing to non-contact deposition and ability to print on non-planar surfaces. Prior work on aerosol-jet print processes primarily focuses on single-layer printing, taking into account different parameters such as mass flow, line width, sintering conditions, and overspray. Flexible PCBs in complex applications are envisioned to be multi-layered, involving stacking of interconnections and connection between successive layers through use of z-axis connections. Aerosol-jet printing method allows the printing of interconnections with a number of inks including silver, copper, and carbon with fine lines and spaces in neighborhood of 10μm. Process recipes for manufacturing multilayer circuits and system scale-up methods are required. The objective of the paper is to establish process-recipes for z-axis interconnects and quantify process variability with Aerosol-jet print process needed for high volume scale-up. Conductive interconnects have been printed using the ultrasonic atomizer and the interlayer dielectrics have been printed using the pneumatic atomizer. The effect of thermal sintering on the performance of the printed circuits has been quantified through measurements of interconnect resistance and shear load to failure. This paper explores the printing of multi-layer upto 8 conductive layers. Sintering profile for lower resistance per unit length and higher shear load to failure was tested.