Dear Michael! Perhaps you did not see my question. Very sorry for this. I mean for a published paper from a journal. Some well-known researchers have co-authorship in papers that are irrelevant to their expertise. Hope to see that.
I think it's ok. I collaborate with engineers and medics designing parts for the body. The human skeleton is a mechanism with a geometry, mechanical properties, etc. You can calculate loads, reactions, displacements, etc.
Once a fellow lecture approached me for a paper in the solar energy cell felid from a Materials Engineering point of a view I found it hard I felt there is no mutual ground in scientific point of view we had different paths so it never finished .so it depends how close you are from the other side