Music Box

Made by Shapekit. 3D viewer, colour preview and more free models: https://shapekit.cc/music-box.html A music box you program yourself. The drum has a hole for every note at every step, 960 in all: push short pieces of filament into the holes, turn the crank, and the pins pluck a printed comb of 15 tines, two octaves of C major. The ZIP has pin charts for Ode to Joy, Twinkle, Twinkle, Little Star and Frère Jacques as a round, and a blank one for your own tune: wrap a chart round the drum and push a pin through every dot. The comb is printed PLA, so it sounds softer and rounder than a steel music box, and you tune each tine with a file and a tuner app. - 8 printed parts

- 12 × 11 × 11 cm assembled (L × W × H)

- ≈ 0.2 kg filament in total

- 56 mm height of the frame, the tallest part (94 × 144 mm on the bed)

Parts Case: A closed box under the frame. The frame plate on top of it is the soundboard; the box gives the notes their body. Four bosses in the corners take the screws. - Size: 116 × 94 × 25 mm

- Print: Open side up. No supports.

- Filament: ≈ 63 g

Frame: The plate, the two cheeks that carry the drum and the crank, and the block the comb is screwed to, in one piece, so the drum and the comb always line up. The rosette of holes lets the sound out. - Size: 116 × 94 × 53 mm

- Print: Flat side down. No supports: the holes in the cheeks have pointed tops.

- Filament: ≈ 61 g

Drum: 960 holes, 15 notes along it and 64 steps round it, for the pins that play the tune. The 56-tooth gear is part of it. Numbers on the far end count the steps and a notch marks where step 1 starts. - Size: 73 × 72 × 72 mm

- Print: Gear down. No supports: the pin holes have pointed tops and the far end closes with a 45° cone.

- Filament: ≈ 100 g

Comb: 15 tines tuned to two octaves of C major, from C4 (38.9 mm long) to C6 (19.4 mm). A groove on top marks each C. The slots let it slide 2 mm along the tines, so the pins meet the tips where they should. - Size: 63 × 58 × 6 mm

- Print: Flat, tines on the bed, at 100% infill and 0.12 mm layers. In PLA: the tine lengths are worked out for it.

- Filament: ≈ 14 g

Crank pinion: 14 teeth on a 6 mm shaft that runs through the cheek: four turns of the crank turn the drum once. - Size: 21 × 20 × 18 mm

- Print: Gear down. No supports.

- Filament: ≈ 2 g

Crank arm: Fits the hex on the shaft, held by an M3 × 8 and a washer. The peg at the other end carries the knob. - Size: 42 × 23 × 14 mm

- Print: Flat, peg up.

- Filament: ≈ 3 g

Knob: Turns on the peg of the arm, held by an M3 × 8 and a washer. - Size: 16 × 13 × 13 mm

- Print: Standing up.

- Filament: ≈ 2 g

Pin gauge: Cuts the pins to length: stand it on the table, push filament down a hole until it stops and cut it off flush with the top. Every pin comes out 6.5 mm long, so it sticks out 2 mm from the drum. - Size: 34 × 14 × 12 mm

- Print: Flat. Not part of the box: only in the download.

- Filament: ≈ 3 g

What else you need - 86 mm of 3 mm steel rod for the drum to turn on.

- 1.75 mm filament for the pins, 6.5 mm a pin: Ode to Joy takes 46 pins, about 30 cm. Any colour that stands out against the drum.