I've been printing a variety of 3d models of whistles, and needed a model that printed 'fast.' Watching how the various whistles I had printed did that I decided to try my hand at designing my own and this is what I ultimately ended up with.

Because the inspiration (which I don't see a public model of, but I may have missed it) uses a dual chamber for resonance, I decided to try something similar that uses two different sized chambers to get an approximation of the step difference between 2 notes in a Major chord. I also needed something to do while the printers were busy printing the previous models. I do not consider this as a quality musical instrument, I do think it has better sound characteristics than many whistles I've seen.

This is small enough to be used as zipper pulls with a ring or cord to attach to the zipper , or may almost disappear on a key ring. Add to a lanyard. hang on the jym bag to have if you end up coaching or umpiring. keep a couple with your hiking and camping kit for use if you discover you're lost. They are also handy for signalling over longer distances and in noisy environments.

If you just need 1 or a few, this may be a decent way to print off some of those spool remnants that you don't want to give up on.

Fast? I have a plate printing on a Bambu Lab A1 Mini with 36 whistles that will take 3 hours, 17 min. another plate of 68 on a Bambu Lab P1S that is going to take 6 hours 54 minutes. This is about 15% faster than the next fastest model I've worked with. I'm sure it's not the fastest or best models, and you may get much better results from a resin printer or Voron, but for my needs this is faster than I was getting.

While I don't advise using this for serious work, the hex hole should be a good fit for a quarter inch hex drive bit. That may be an OK method of opening up the whistle if push comes to shove.