Don't Let Precision Engineers Spec Leather Parts!

The customer provided very clear requirements: make the part with a maximum profile of .030 inch. The part could not interfere with the aircraft control. Not hard for an injection molded or cast aluminum part - but this part is also covered in padding and leather.

It is hard to model in Solidworks correctly how leather and padding are going to behave in real life. So I did my best with surface modeling of the assembly then scanned one of our first production parts (see the image below). The 3D scanner data was converted by me into a usable solid model. I imported the model into the Solidworks assembly. With the imported part in the assembly, we can see how the leather cover interacts with the aircraft controls and the model matched the physical part. The controls were fine. The physical model and predicted Solidworks model were more than .030 inch different in places.

Sometimes, we (designers) are so used to our experiences that we forget that other worlds exist. It would have been better for everyone involved in this process if the design engineer had collaborated with others who deal with leather and foam to determine the practical requirements for the design.

bell 525 scanned armrestjpg