Ahoy mateys! The Cap'n Crunch Bo'sun whistle, originally a prize toy in boxes of cereal, became the stuff of legend as a tool for phone freaks (phreakers) delving the depths of telecom networks in the 1960s. Because it emitted a tone of 2600Hz, the same tone used by AT&T's system to signal a line to open and prepare for connection, it could be used to manipulate the system and make free calls. The 2600Hz signaling protocol is no longer in place, but phreakers' use of the whistle remains a touchstone of ingenuity in the history of hacking. Re-live the excitement with this 3D printed replica!
Compare the sounds of the original and printed whistles here: https://youtu.be/2qwcc3cKmsA
The fabled phreaker John Draper, who popularized use of the Cap'n Crunch whistle for network exploration, shows how he used to open a phone line and dial a number in this video: https://vimeo.com/112783389
- Orient the whistle mouthpiece down
- Include a skirt starting 0.00mm from the object with 4 layers and 25 outlines
- Use 100% infill
- Add external support only (Internal support will block air flow and the whistle won't work)
- If you print in abs, smooth the whistle with acetone to get a great sound
- Getting a perfect 2600Hz pitch is a challenge - scale your print to different sizes to
tweak it up and down
Update: Andy Cohen, cohost of the 3D Printing Today podcast, kindly sent me a repaired version of the whistle mesh that resolves a number of problems with slicing. It is the best one to print.