[MikeDubreuil]

#1 Rule: only have an experienced welder weld your robot frame.

Our robot is welded by a grad student who is on Northeastern's Mini-Baja team. He's been welding for years and is very proficient in welding aluminum because of aluminum tubing being used in their vehicles frame.

We were mentoring a rookie team and they had an inexperienced person weld their frame. It was disastrous and the frame broke apart before the build season was over. Our Mini-Baja guy cut all the old welds away and did it correctly. They never had another problem.

I would say if you don't know of anyone who is experienced on your team then you should call up local machine shops. Even if they won't do it for free the last thing you want to happen in competition is a broken weld.