I was trying to compare my hand calculations to Solidworks FEA and I was always getting a discrepancy in bolt factor of safety. I dug into it deeper and realized that Solidworks calculates bending stress for a bolt using its nominal radius for area moment inertia and stress calculations. Is there a reason for this that I cannot think of? I have been using the minor diameter to be conservative and do not know what the correct radius would be but I am pretty sure a bolt does not have same bending strength as a solid cylinder(unless analyzing portion with no thread).

hi tyler, can you point us to the reference you found for solidworks simulation and also the reference for the equation you're using?

your methodology sounds logical and i don't think it hurts to look at it from both perspectives.