This has absolutely nothing to do with coffee but I needed a venue to show off the automatic chicken coop door that I "invented."
This past winter I set my mind to building a chicken coop door that would open and close automatically. You can buy battery or solar operated doors but I wondered if it was possible to do it without electricity. It occurred to me that the chickens can create "potential energy" by flying up to a perch. If I could design the perch to channel that energy into the closing of a door and calibrate it perfectly according to the total weight of my flock, then I would have the perfect system: the door will never close before the last bird is in and it will always close immediately after the last bird perches for the night.
I mounted the roosting bar on a sliding track using a ball-bearing shelf bracket from Home Depot. The bar is attached by rope to pulleys hanging over the bar and over the door. I knew that a big challenge would be getting the weight calibrated correctly and that it needed to be adjustable to account for a changing flock. To that end, I secured some heavy chain-links to the door side of the rope and used carabiners to attach milk jugs full of water, which can be easily removed to add/subtract water.
In testing the system with bricks (one brick equals approximately the weight of one bird), I was surprised that if it took six bricks to make the door close, I likewise had to remove ALL six bricks to get it to open. There must be a LOT of tension in the system that has to be overcome. I'm using fairly cheap pulleys, so that must be part of it. It actually works out for the better, since I don't want the door to open if for some reason one chicken leaves the perch in the night.
The real adventure was training the hens to actually sleep on the bar. The challenge was greatly compounded by the fact that I was integrating two mature hens (the Americaunas) with four pullets.
After building the new coop and new door, I transferred the two hens first, while the pullets remained in their original quarters under a heat lamp. I calibrated the door weight for the two hens. They did not want to use the bar but instead favored the nesting boxes, which was more similar to the sleeping arrangement they had gotten used to in their old, small coop. I began a nightly routine of literally moving them onto the bar. They hated this but once on the bar, they usually settled in. I can't remember exactly but I think it took around two weeks of this before they started choosing the bar. I got the door to close reliably with two hens, however, to my chagrin, it would not open even with both hens off the bar and one on top of the trap door.
It seemed that the system would work better with more chickens, so soon I attempted to add the four pullets (they were about two months old). I had raised them adjacent to the mature hens in hopes that they would all be used to each other's presence but, alas, the hens terrorized the pullets all the same. The pullets were interested in the bar but would invariably get pecked off by the hens. They discovered many other suitable perches inside the coop. The base of the coop is made from pallets and they much preferred to roost on the rim of the pallets given the safe distance from the Americaunas. I realized that for my door to work I'd have to deprive them of any other suitable perch. I did this and again began the ritual of physically placing chickens onto the bar. It was rough, especially for whichever chicken was placed next to the grown hens. I decided to a add a middle bar so that they would have another option away from the hens. This was somewhat helpful. The hens would typically grab the low bar and then the pullets would jump for the middle bar. But once the bar dropped and the door closed, the hens would hop off the low bar, jump to the middle and begin their reign of terror all over.
It took quite a bit longer than I expected for things to settle down, like in the range of 2-3 months. The pullets were growing so I had to keep an eye on the door and add water to the milk jugs as needed for. Now they are all full grow, laying beautiful eggs and the door has been working great for about two months. I did discover one major flaw in this system, which is that if a hen goes broody she will not use the perch. This happened recently but the broodiness lasted only three days with me continually stealing the poor girl's eggs out from under her. I was able to close the door manually those three nights and the weight of five chickens was more than enough to keep the door closed through the night.
I like to say that I "invented" this system because after I thought up the concept of using a roosting bar and gravity to close a door, I did some online searches and didn't find any examples of a chicken-powered automatic mechanical door opener/closer. It turns out I wasn't using good search terms because later I turned up a number of examples. Figuring it out on my own did make for a somewhat unique design.