Making a "wayang kulit" figure that is suitable for a performance involves hand work that takes several weeks, with the artists working together in groups. They start from master models (typically on paper) which are traced out onto skin or parchment, providing the figures with an outline and with indications of any holes that will need to be cut (such as for the mouth or eyes). The figures are then smoothed, usually with a glass bottle, and primed. The structure is inspected and eventually the details are worked through. A further smoothing follows before individual painting, which is undertaken by yet another craftsman. Finally, the movable parts (upper arms, lower arms with hands and the associated sticks for manipulation) mounted on the body, which has a central staff by which it is held. A crew makes up to ten figures at a time, typically completing that number over the course of a week. However, there is not strong continuing demand for the top skills of "wayang" craftspersons and the relatively few experts still skilled at the art sometimes find it difficult to earn a satisfactory income.