When assembling the rivet gun, when should you attach the air line to the rivet gun?

Attaching the air line to the rivet gun after the assembly is the preferred practice because it ensures that the tool is not inadvertently activated while you're still handling or adjusting it. This is crucial for safety reasons; having a powered tool in hand can lead to accidents if the tool accidentally fires. By connecting the air line only after you have finished assembling the rivet gun, you minimize the risk of unexpected operation.

Furthermore, this approach aligns with best practices in tool handling, emphasizing control and caution to ensure both the safety of the operator and the integrity of the work being performed. This methodical approach also helps in confirming that all parts of the rivet gun are correctly installed and functioning before applying power.