Friction-stir welding (FSW) is a solid-state joining process that uses a third body tool to join two faying surfaces. Frictional heat between the welding tool and the work pieces causes the latter to soften without reaching the melting point, allowing the tool to traverse along the weld line. In this work, CNC Milling Machine is used to weld the parts together. The parts being welded are aluminium alloy AA5086 H32-AA6061 T6. The detailed mathematical model is simulated by Minitab17. In this investigation, an effective approach based on Taguchi method, has been developed to determine the optimum conditions leading to higher tensile strength. Experiments were conducted by varying rotational speed, transverse speed, and constant welding depth using L9 orthogonal array of Taguchi method. Effect of different tool pin profiles on the quality of the welded joint is also studied for welding. Different tool pin profiles considered are threaded, taper, circular/round and square. The tools are designed using Pro/E and are manufactured on a Lathe machine. After the parts are welded, various practical tests are performed on the welded parts that include the tensile strength and the Vickers’s hardness test.