Boydster,

Agree completely ... The discussion/analysis started to determine whether a bolt through the entire tube set is stronger than two bolts on one side of the roll bar attachment. Some have used two bolts, or more properly screws, where the inner tube is drilled and tapped to accept the thread of the screw.

My intellectual curiosity and the fact that health issues prevent me from getting back building the car ... drove me to see if I could figure out ground truth.

What I believe it comes down to:

1. Because of the ultimate tensile strength and shear strength of the roll over bar materials (304 SS) ... the point of failure is the bolt;
2. The shank of the bolt is stronger than the threaded portion of the bolt;
3. That during a roll over the forces and direction of application to the roll over bar will vary considerably during the actual roll and will therefore not be axially down the roll bar tube;
3. The larger the diameter of the bolt ... the greater its shear strength is; and,
4. More bolts connecting the tubes assuming the tube integrity remains the same ... increases the shear strength of the assembly.

Do you agree?

Clearly in some ways this is just mental gymnastics ... but kind of fun mental gymnastics for this old mechanical engineer.

Carl