Forming welded steel rods

I am working on something with a rectangular frame modeled with .250" steel wire.  It will have a series of slightly smaller steel wires welded across in both directions and the finished part will need to be domed.  I can currently create a blended surface, flatten it and create my model and then form it back.  Does anyone know of any way to model the part formed as I currently have it and then flatten it to the exact size it will be before it's formed? Basically, I need to reverse engineer the development of the part to know what geometry to start with in the flat (accurately) to end up with the proper finished part after forming.   I don't think it currently reflects what I would see in real-life.