Care must be exercised in taking apart, for if the box is wound up and the fly is removed, the cylinder is ruined. The spring relaxes at a bound, causing the cylinder to turn with such rapidity that the pins cannot resist the teeth, whose force is intensified by the velocity of the cylinder. The pins originally bent forward are broken, or pressed backwards; as they are hardened, they cannot be bent forward again without breaking. This accident involves the cost of a new cylinder, the most expensive part of the apparatus. Besides, the comb almost always loses some teeth and the wheel-work also suffers in its turn.

To avoid such mishaps the careful operator will take the parts asunder in the following order:

1.   Remove the comb.

2.   Take the apparatus from the box and completely disarm the spring.

3.   Remove the barrel.

4.   Remove the escapement.

5.   Remove the cylinder.

The barrel and the wheels are cleaned like those of a watch.

The cylinder should be handled carefully. The holes should be well cleaned. Oil should be put only on the pivots, especially none on the part of the arbor to which the cylinder is attached. It is the first piece to be replaced, care being taken to see that the arbor turns freely, but without play, between the bridges. When it is in position, put in the escapement, then the barrel, and finally the comb.

The comb, representing the musical part of a simple box, cannot receive too much care. Before replacing it examine the springs closely, and in supplying the ones that are lacking, take for the model of size and form those resembling them the most. If the parts have been put together properly, then, as soon as the comb is screwed in its place, these should be found in good working order: the levee (lift)—that is, that the pins do not lift the teeth too much or too little; the tombée (fall)—that is, that the chords, the bass, the medium, and the treble, fall together; and the visée (pointing)—that the pins catch at the center of the ends of the teeth.