So I've read quite a bit about coop construction. One thing that really stood out to me was using pennies as washers to hold hardware cloth. Some have said that reactions in the metal would cause it to rust, etc. I've heard the same thing about copper pipes in walls and other examples. But what I keep thinking is that the hardware cloth is galvanized. That means hot-dipped in zinc or chemically bonded to zinc right? Pennies haven't been made out of copper for some time, but rather have a large zinc makeup. So technically speaking, shouldn't a non-copper penny be fine as a washer? If so, does a person drill pilot holes in each penny or do you use some type of self-tapping screw? I'm confused...?