In this project, CNC Milling Machine is used to weld the parts together. The parts being welded are made up of dissimilar materials aluminium alloy AA5086 H32-AA6061 T6. The rotational speed is varied from 900 rpm to 1500 rpm while the welding speed is varied from 20 to 40 mm/min. The other parameter involved is the tool profile. The dimensions of the parts are (300mmx30mmx5mm) which are welded to form a butt joint. The effect of different tool pin profiles on the quality of the welded joint is also studied for welding. Different tool pin profiles considered are round threaded, 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. The experimental results proved that the highest tensile strength of the welded joint i.e., 28.65 N/mm2 was achieved with the square tool profile at speed 1200 rpm with feed 40 mm/min and the highest hardness value of 58 HV was achieved with the round tool profile at 1500 rpm and feed of 40 mm/min.