I was wondering why chassis' are made from round tubeing instead of square tubing? Is it because of the angles that some joints end up at, is it stronger than square, more felxible than square, etc. Also, when the term "moly" tube is thrown around, are you talking about 4130? What diameter and wall thickness is used?
For any given weight a circle is stronger than a box or rectangle. The box will more easily deform because of the flat surfaces. IF the chassis builder does a proper job of notching the round tubes for a exact fit the pressures exerted on the side are more evenly distributed. Chassis flex can be built into any structure, The round tube will take repetitive flex many more times than a square tube chassis, again when properly engineered
