The Tempest Super Whistle

thingiverse

My attempt to reverse engineer the world's loudest whistle. How I Designed This I googled some images of the original whistle, estimated its size and guessed what was inside. I drew the design in FreeCAD, and sliced the STL with skeinforge. My first design was a two-part print - base and lid - which had to be glued together. It did not function as a whistle at all - it only hissed. For my second attempt I tried printing it in one part. I also redid the interior, which worked quite well. On the third go I only cleaned up some minor mesh flaws and increased the pea size. This seems to have the opposite effect to the one intended. I also printed this in 0.3mm layers. Instructions No raft needed. Just print the first layer at half speed. Print the pea first. Drop it in place when printing has exceeded 50% - when the ring tab starts printing. Print the 10mm pea with a 0.2mm layer thickness for best results. The whistle prints quite nicely at 0.3mm per layer. My slicer removed the temporary internal supports; I guess I have to make them thicker. I used PLA extruded at 215 C. This tented the top layer just fine.