I'm curious if anyone can provide any input on how Solidworks calculates the torsional constant and max shear stress distances for beam cross-sections. I've run numerous beam torsion tests on thin-walled open and closed sections, comparing them to hand calculations and solid models. For most of the open sections, I've found relatively decent agreement between the software's torsional constant calculation and the hand calculation, where J is found for the profiles by either unfolding or breaking them into individual rectangles. However, in these cases, the max shear stress is based on the thinnest section thickness, and the software's "distance for max shear stress" is generally off by a factor of 5-10x, resulting in huge simulated torsional shear stresses. Can anyone provide any insight?