A novel friction stir welding technology known as bobbin tool friction stir welding (BTFSW) has been invented, allowing this process to be carried out with zero vertical force. Another benefit is the simultaneous double-sided welding and symmetry of the stirring zone along the thickness. The purpose of this study is to explore the adoption of double-sided friction stir welding technique using a floating bobbin tool for welding Al–Mg aluminum alloy. At the same time, Al–Mg alloys were subjected to gas tungsten arc welding (GTAW) in order to compare the findings and demonstrate the dominance of these new technique. The bobbin tool features two shoulders and a triflute pin that is threaded. To assess the quality of the joints, non-destructive tests of visual inspection and radiography, as well as destructive tests of tensile, bending, hardness, and metallography, were performed on the welded samples after the welding operations. Non-destructive tests, on the other hand, proved the perfection of welded samples with appropriate parameters. The tensile test findings, on the other hand, revealed that the joint efficiency of BTFSWed was extremely significant and reached around 94.5 percent, whereas GTAW-welded samples only achieved 37.7 percent. The nature of their microstructures was attributed for the majority of these disparate results. Metallographic analysis demonstrated that homogeneous ultrafine equiaxed grains of BTFSWs exceed inhomogeneous coarse dendritic grains in terms of mechanical qualities. Accordingly, the development of the BTFSW process opens the door to the development of a low-cost solid-state welding technology.