We choose the best aluminum extrusion welding based on the specific project. Generally, we consider factors such as cost, repeatability, expected weld performance, and production speed. Others are the safety of the process, geometric limitations, and tolerance for distortion. It is important to consider these factors because welding aluminum can be challenging. You are looking at issues such as hot cracking, high thermal conductivity, oxidation, and porousness. The fact that the thickness of the aluminum extrusions can vary a lot makes the process even more challenging.