I saw a similar feeder here (can't find the thread right now) and decided to build one. I purchased 3" PVC (about $10 for 10') and two 45 degree bends as well as a cap. My coop is elevated with an enclosed run under it (great for short vacations so I don't have to have a chicken-sitter come and let the girls in and out). I mounted a corner litter pan under the coop (from PetSmart. It's for rabbits, guinea pigs, etc.) and just ran the PVC down into it. The PVC sits about 1/4" above the bottom of the pan. I could have run a straight pipe down, but the coop prevents that. I used the 45 degree bends to prevent the feed from getting blocked. I have seen the feeders where people put a sort of U bend on the bottom, but I didn't want to do that do to the possibility of water build-up. Having the feed drop out the bottom allows me to make sure they're always getting fresh food.
