Tube Frame

A tube frame or space frame is a chassis constructed from rigid truss members attached in a three-dimensional structure with the body panels having little or no structural function. Stiffness is maximised by triangulating the tubing to ensure that the tubes are not loaded in bending.

Design

Designing the tube frame is a compromise between structural rigidity, weight and manufacturing complexity.

Triangulation

Proper triangulation makes sure that the tubes are not loaded in bending. Full triangulation is probably impossible given that the driver like, can't have a frame member through their torso, but please try?

Manufacturing

Cutting tubes

Tubes can be cut by hand, using holesaws and a drill press, or by using water jet or laser jet cutting.

Tube bending

Bending the tubes by hand

Using CNC tube benders

Any motorcycle builders around? They can have tools for 1" tubing.

Fixtures

Fixturing is central to the accuracy of the finished tube frame. Fixtures can be made in MDF, plywood or sheet metal.