I needed a self feeder for my cat, so he would stop waking me up. After looking around on the Net (and instructables) I did find one that I based this feeder on, in a book called (Snowball Launchers, Giant-Pumpkin Growers, and Other Cool Contraptions by Tom Fox) I take no credit for it. Just didn’t like the idea of using cardboard. I also wasted a lot of time trying to use electric motors and timers. This was a much better idea and has been working well so far.
That’s it, now just thread the bottle into the inside of the container, run the rubber band with the ball into the bottle and pull it up to the hole in the lid clipping it with the paper clip. Update.... the top turned out to be to thin, so the clip was replaced with a PVC pipe.
Use the screws to mount it to something solid, and high enough to remove the lid. The edge of his play tower worked out well. If you need to I’m sure you could mount it to the wall with a block of wood.
Training was pretty easy. Show your cat that food will fall each time the ball is pushed or pulled down. With Apollo, it took one time. One problem I did find is he will pull the clip off the top dropping the ball, but only when he runs out of food.