# Failure due to shear stress on rod lip?

Let’s say I have a circular rod that has an outside lip with a larger diameter and certain height. The rod moves axially, and the intent of the lip is to mechanically stop the rod at a maximum axial displacement. How would I calculate the maximum static axial force I could apply to the rod before the lip shears off of the rod?

I have a pretty good understanding of how to apply this problem in a simple cantilevered beam with a load orthogonal to the beam surface that provides a shear stress, however I can’t seem to wrap my head around this kind of problem, especially regarding second moment of area with a cross section that is radial instead of on a constant plane. As far as I can tell, the process is:

1. Draw a FBD to find resultant forces on the shaft.
2. Determine the resultant normal and shear stresses due to axial, shear, torsion, and bending forces.
3. Use Mohr’s circle to determine sigma max, sigma min, and tau max.
4. Apply one of the failure criteria for brittle/ductile materials.

Can anyone provide some guidance or direction?