Recently my wife asked me if I had some idea how to prevent the crow birds from stealing the suet cakes that she usually hangs on the trees to feed the titmice and other small birds during the winter season...

So the goal of this project was to create a container for suet cakes (or fat balls) for feeding titmice and other small birds during the winter. The container should be strong enough to prevent larger birds to "steal" an entire fat ball and fly away with it.

The feeder consists of a base plate, four separately printed side walls and a top cover. The feeder is assembled by "clicking" the plastic tongues on the left of each side wall of each into the corresponding slots of the neighboring side wall. Before closing the walls by clicking the forth wall into the first, the socket of the base plate is inserted between the walls. Due to the conical shape of the socket, it will hold in place and not fall out. Finally, the top cover is sled over the two upper hooks of the side walls. A cord is attached to the hooks, which can then be used to hang the feeder on the branch of a tree.

The top can easily be lifted along the cord in order to fill in the suet cakes or fat balls. The conical shape of the feeder causes the the fat balls to slide downwards as they get smaller while being eaten up by the birds. This way, they stay always accessible through the grid mesh until they are small enough to fall out through the bottom hole.

The included SCAD source file is fully parametrized and commented. Thus, if the ready-to-print STL files do not exactly fit your needs, you can easily modify the source to adapt it. For printing the complete titmouse feeder, you need to print 1x base plate, 2x side wall without hook, 2x side wall with hook and 1x top cover.