Train Whistle Chuck Jig

The whistle drill chuck is used to drill four holes in a 2 by 2 blank to be turned to make a Whistle. The chuck requires two 3/8 inch 16 TPI bolts. If using a threaded rod instead of the bolts, you can print the screw caps file to cap the rods. The print settings are what I use. When slicing, you can use different settings based on your 3D printer and filament used. The threads will come out pretty tight, so you may have to use a die to ream them out slightly.