I built a couple of hi-cap chicken feeders this weekend. I don't have pics here but I'll try to post them tonight.
I started with 6 foot long 7" diameter A/C conduit and cut it in half to make two 3 foot tall feeders. I cut rectangles out of the bottom of the "pipe" with snips. The result looks like the top of a turret on a castle with several tabs sticking up. I used pliers to fold the edges where I cut them so they are smooth and won't cut people or chickens.
Then I folded the end of each of the tabs down and punched a hole in it using a concrete nail as a punch. I had some pressure treated lumber to use as a base and a new plastic oil pan to keep the feed from being scattered too easily. I put deck screws through the holes in the tabs and the oil pan into the wood. That gives a little weight at the bottom and raises the pan up off the ground. I drilled a number of small holes in the pan to drain out any rain that gets in so the pan won't fill up.
I wired them into the corners of the pens and currently have a couple of spare plastic buckets to cover the top to keep birds/rodents/chickens/rain out.
When I have time and money I'm going to add an elbow to the top and have it come out the side of the pen so we can fill the feeders from outside the cage. I'll have to build a cover of some kind to keep birds and rodents out. Maybe some of the leftover steel roof material with wire for hinges and a wire to keep it shut.
Then we will be able to feed and water the chickens and get the eggs without having to go inside the cage. That is nice when it rains.
3 hours ago