using 22 gauge wire, 1.5" exposed on each wire in a looping grid pattern, with 8 layers of plastic wrap, I successfully built a force sensitive resistor. Freaking sweet.

Using the same grid and wire, I built one using the foam. Functional and works.

I'm not really sure which will be better in the long run. The plastic wrap will run the risk of becoming damaged by extended use. The foam sensor is a just bigger since the foam is 1/4" in height.

I still haven't attempted to daisy chain them together also to test out my baseball diamond idea.