BJD stands for Ball-Jointed Doll. These dolls are an expanding art-form with a rich history and incredible versatility
A BJD artist needs to be sculptor, designer, and engineer all at the same time. Dolls are usually created by one artist who spends years (and a great deal of money) honing their craft. Some are made on contract for companies like Cerebrus Project, Volks, Luts, Soom, Iplehouse, etc… Others are made available by the artist themselves, as is the case with Bimong, Dollshe, Dust of Dolls, EOS Doll, Supia, etc… A single doll usually takes months to develop, and can be in production for years. The finished result is called the master sculpt and is used for casting. This master is typically crafted either in clay or via a 3D sculpting program.
BJD are typically cast in polyurethane resin*, a durable but volatile and expensive material that lends itself well to customization as it can be sanded, modified, painted, and repainted. Given the volatility of the process and limitations on space, staff, etc, the casting process can take months or, in the case of backlogs and setbacks, even years.
Once cast, resin BJD are distinct from most dolls in that they lend themselves to complete customization. While dolls are often sold as completed “full sets” by companies, blank dolls are also available. A blank doll must be completed with the assistance of other artists (like me) or by the owner themselves. Clothing makers, eye makers, wig makers, and painters all play a roll in completing these dolls. Because of this customizable nature, BJD owners can purchase a one of a kind collaborative piece of art.
*Some artists work in porcelain as well. These dolls are basically always one of a kind artist fullsets because of the nature of the material.
Companies have proprietary sizes that can be divided into common scales: so a Super Dollfie from Volks is 1/3, a Mini Super Dollfie is 1/4, etc… Other lines have different names or just use the scale. Sizes here are averages; individual creators pursue their own stylistic variations involving scale/size.