What is the weakest fin attachment method that may not be strong enough for high power rockets?

The method of attaching fins to the motor tube through fin slots in the body tube is considered the weakest attachment method for high power rockets because it relies heavily on the structural integrity of the body tube and the alignment of the fins within the slots. In high power rocketry, the aerodynamic forces during flight and the stresses upon recovery can be substantial. If fins are merely inserted into slots, they can be subject to shear forces that may compromise the attachment, especially if the bond is not reinforced with a stronger adhesive.

In contrast, methods that involve more robust bonding, such as using epoxy with fiberglass reinforcement, create a much stronger connection that is capable of withstanding the greater stresses experienced by high power rockets. Attaching fins with screws, combined with wood glue, also enhances the structural integrity by providing mechanical fasteners that help maintain alignment and support the fins during flight. Overall, methods that utilize strong adhesives and mechanical support are essential for ensuring the durability and performance of high power rocket fins.