A friend who keeps a parakeet asked me to build an automatic feeder.
The idea: dispense food gradually over time, so the bird can be fed in small portions while the owner is out.
From a quick search, I couldn’t find an off-the-shelf product that “dispenses a fixed amount in small portions over time.”
Same story for goldfish and tropical fish auto-feeders — most just dump the entire portion at the scheduled time.
I made this one for a parakeet, but it should work just as well as a fish auto-feeder for goldfish or tropical fish.
If you’ve got a bird or fish and you’ve been thinking about building your own auto-feeder, hopefully this gives you a starting point.
The Finished Auto-Feeder
Here’s the finished version up front.
The food sits in small compartments around a circle. The whole tray rotates slowly, dropping a portion at a time as it turns.
The rotation is driven by the hour hand of a clock movement.
The 3 compartments shown release their food over roughly 6 hours.
I shot a time-lapse of the food being released:
Building It
From here on, the build process.
Credit where due: the idea of using a clock movement as the drive isn’t mine — I heard about it from “a friend of a friend’s veterinarian’s friend” who built one this way. I’m just borrowing the idea.
Drive unit and food container
＜Drive unit＞
The drive uses a clock movement.
I bought a clock at the 100-yen shop.
What I’m using is the movement (the black part inside).
＜Food container＞
For the food container I picked up a circular compartment box called “Petit” at the home improvement store. It’s normally sold for storing small fishing tackle.
It’s divided into pie-slice compartments around a circle:
Same product is also available online:
Fabrication
The joint between the rotating shaft and the food container will be a small piece of wood.
Cut a piece of scrap wood with a hand saw.
Sized so it fits into the central well of the food container:
On the clock side: the movement has the hour hand and minute hand on stepped concentric shafts that rotate at different speeds.
The hour hand sits on the rear (deeper) step.
To rotate at the same speed as the hour hand, the wood block needs to engage that same step.
Measuring the inner diameter of the hour-hand mount: 5.5 mm.
So drill a 5.5 mm hole into the wood block, matching the hour-hand shaft.
Test-fit it onto the clock movement.
Snug fit!
Now when the clock runs, the wood block will rotate at hour-hand speed.
Now to join the food container to the movement.
Design goal: it should be removable
If the container is permanently glued to the movement, refilling the food becomes a hassle.
So I want a one-touch attach/detach.
Solution: magnets.
Pulling out a small magnet from my parts bin (bought it for a different project a while back):
The food container has a recess in the center — perfect spot to mount the magnet.
Drop the magnet in with glue and cover with a thin plastic sheet (I cut up the plastic packaging from an SD card).
Magnet seated, glue applied…
Capped with the plastic sheet. Wait for it to cure.
Meanwhile on the clock side: I added a steel screw to the wood block that the magnet will grip.
Magnetic coupling ready.
…wait, I forgot something important.
The food has to actually fall out when the container rotates — so I need to cut a hole in each compartment.
Cut the holes with a utility knife. (Watch your fingers.)
Same hole in each compartment.
Glue the clock movement onto a wooden base. While the glue cures, I painted the base white.
Onto the rotating shaft…
…attach the food container.
Done!
Done!
The magnetic mount makes refilling food easy — just lift off, refill, snap back on.
＜One important note＞
If you force-rotate the food tray by hand while it’s mounted on the clock, you’ll strip the clock movement. (I’m not putting that in the main article — but I learned this by killing my first prototype.)
To set the rotation position, use the time-set knob on the back of the clock movement.
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