Per the structural fiberglass manufacturers web site, these components can be mechanically connected. My plan for the production of the Auto X-Prize car line, was to quick connect the tubes with sheet metal and rivets, and then down the line the joints would be covered with fiberglass and or carbon fiber.
Welding is a craft, good welding is an Art. Welding a space frame car involves vertical and overhead welds, unless a means to rotate the frame is available, a car rotisserie. Fiberglass work is labor intensive, but the actual labor is low skill. Today I think I may try to use PVC fence rails to fab the chassis and then fiberglass over the joints with multilayers at the joints. I'll get some and try some sample joints....to be continued.
