Along with a deer feeder that I turned into a chicken feeder, I have several pvc feeders Exactly like yours, they work GREAT. I like the hinged 2x4 support, that's a great idea. One suggestion that might be useful to you, a pvc grate drain with a hole cut out just large enough for a chicken to get her head through. Lowe's and Home Depot have them for about $2 each. It will prevent your hens from slinging the feed all over the ground. It should slip right inside the end of the Y, and no need to glue it.
Your Dad and Son did a really nice job for you!