[Rod]

Originally Posted by KenWittlief

Pins are one of the weakest ways to go. Its difficult to calculate the impact shear forces a pin will see, in a collision for example.

Ive seen many axel pins break, and Ive seen a 0.5" diameter axel break where the pin was located, due to the reduction in cross sectional area the hole produces in the shaft.

BTW, they use pins on the props for small outboard motors - and they call them shear pins - they are intended to break if the prop hits a rock - saves the prop

A robot with failed drive train, motors spinning and bot going nowhere, is one of the most common failures you see at FIRST competitions.

Ken,
Are you are speaking of a pin located perpendicular to a shaft, as is the case of a prop shear pin, or a pin located parallel to the shaft, as the drawings show? I do not disagree with you, just want a clarification.