You need to cut the last VERTICAL segment out of each "square" of the panel leaving the horizontal wires sticking out as little daggers. The objective is that when the panels slam together it is seldom an exact match... and one set of wires will fit inside the other's squares. When this happens, there is a kind of latch formed. Also, the amount of overlap on the V entrance needs to be such that it cannot be pushed outward, thus allowing escaping hogs. The trigger I have seen used is simply a stick picked up from the local area which has noches/bumps on it so that it will hold the ends open until a sufficient bump happens. When the hogs slam into the closed end of the V, they are deflected toward the center of the trap.
Let me know how it works... and when you catch enough to have a big BBQ, let me know /forums/images/graemlins/smile.gif /forums/images/graemlins/grin.gif