[EthanMiller]

I'm not doing it as part of a team, but I go through the border both ways every Saturday, with fencing gear, which, including a sword, isn't too different from the robot's difficulties, in my experience.

First, make sure the entire team knows that it's serious. Border guards don't joke, don't appreciate jokes, and take anything said as serious.

Second, answer honestly. They'll ask you about the robot and tools - tell them about the regional, mention that it's for FIRST, and call it a robotics sport (or something along those lines). The guard won't know what FIRST is, but having an international organization provides legitimacy. And the 120-lbs robot doesn't hurt.

Third, don't complain if they want to look at it.

Fourth, if you're going to bring powertools, don't try to hide it. If you don't need to bring them, don't.

Hope that helps - and teams that have done it, their advice should be taken first.