Things You'll Need
Instructions
Collect all the parts you need. The toughest part to obtain is the musical movement. Several companies sell these, and they have thousands of songs. For a few dollars more, you can get a movement with any song. The movement is a compact, self-contained unit; some are sealed.
Decide on the box shape and type. The box does not have to be square. You will probably be drilling a small hole in the box, so wood is an excellent choice; glass or porcelain is more difficult to drill into without shattering the material. The movement needs to fit easily into the box. Some music boxes have only enough room for the movement, but most have extra room for jewelry or memorabilia.
Find the two extensions from the movement: the on/off switch and the winding stem. These are usually rods that extend from the movement. The on/off switch clicks back and forth, and the winding stem rotates. Sometimes the winding stem is a flat-folding key.
Position the on/off switch properly in the box. The switch should be activated when the box lid is opened and closed. Opening the lid turns it on, and closing the lid turns it off.
Position the winding stem correctly. This might mean drilling a small hole in the box so that the winding stem protrudes. If you have this type of a winding stem, the music box can be wound without you opening the box. Some movements have winding keys that fit flat against the movement--in which case, no hole will need be drilled.
Prepare the separator. This is a "ledge" to protect the movement. If the movement takes up the whole box, the separator may be unnecessary. If the workings of the movement are visible (and attractive), you might consider a clear plastic separator. If the winding key is internal, then the separator will have to leave room to easily access the winding key.
Attach all the other parts firmly to the box. Some movements come with tiny screws for this purpose that can be tightened with jeweler screwdriver. Otherwise, the parts can be glued into place.