A 1-in-diameter hot-rolled AISI 1144 steel rod is hot-formed into an eyebolt similar to that shown in the figure for with an inner 3-in-diameter eye. The threads are 1 in-12 UNF and are die-cut. For a...

A 1-in-diameter hot-rolled AISI 1144 steel rod is hot-formed into an eyebolt similar to that shown in the figure for with an inner 3-in-diameter eye. The threads are 1 in-12 UNF and are die-cut. For a repeatedly applied load collinear with the thread axis, using the Gerber criterion, is fatigue failure more likely in the thread or in the eye?

What can be done to strengthen the bolt at the weaker location?

If the factor of safety guarding against a fatigue failure is nf = 2, what repeatedly applied load can be applied to the eye?