Thanks for the replies guys. I enjoy projects like this. Yeah, forge welding the chain is tricky. Especially that last link when you have to hold on to the rest of the chain and keep it out of the way. For this trap I used 1 1/8"x 3/16" bar, 1"x 3/16" bar, 1/2" x 1/8" bar, truck coil spring, 5/8" rod, piece of file, garage door spring, nails, 1/8" sheet, 1/4" rod, 1/8" rod and some rivets. It's nice to have a good scrap pile.