The evolution of a whistle, and a basket I made for a fish tank

thingiverse

The whistle that works is Whistle 4. The ball prints inside, you just have to reach in with a paperclip and bust it off. The whistle shows the great advantage of desktop 3D printing, I designed it and revised it and got it to work all as an exercise, in an afternoon. A fun and satisfying afternoon. The fish tank filter keeps fish from migrating from one tank to another. It goes into the tank and gets two hoses attached to it. It also works, but I changed plans on that tank so no longer use it.