What's better than a whistle? A robot whistle! I print it standing on it's head on my cupcake and it comes out beautifully.

The original wasn't completely manifold. Use the fixed version.

If the whistle doesn't make any noise after it's printed run a small file through the hole you blow into until you've filed off any dangling strings of plastic blocking the hole. This whistle is peircingly loud.

If you're going to work from the sketchup file, you'll need to scale it to .05 to get it to print the correct size. The .stl has already been scaled to this.

The sketchup file was made from importing and cleaning up Madox's original flat whistle stl.