Longhurst Engineering, PLC, and Vanderbilt University propose an in-space friction stir welding (FSW) machine for joining complex structural aluminum components. The proposed FSW machine is innovative because it can be deployed by 2 people and be used to weld complex surfaces that extend beyond linear welding applications. The in-space FSW machine is a 3 axis system that can be mounted to work pieces of varying geometry, position, and orientation through the use of a high performance vacuum system or mechanical clamps. The key enabler of the proposed FSW machine is a self adjusting and self aligning FSW (SAA-FSW) tool that eliminates the need for automated actuators. In addition, a collection of force reduction techniques will be included as part of the system. When combined together, it is theorized that the effect will be significant and will lead to the advancement of FSW by reducing structural rigidity requirements of FSW machines. Our work plan begins by determining the net effect of the combined force reduction techniques. Substantial effort is given to the development of a preliminary SAA-FSW tool which includes experimental welding. Lastly, a preliminary set of engineering plans will be delivered based upon the results from the development of the SAA-FSW tool and force reduction techniques.