Vertebrae challenging to sculpt because there are so many and each in the series is a slightly different shape. If you don't get their individual proportions and the spacing between each exactly right then errors add up. This can result in the body having the wrong shape entirely. Shigeru uses a very neat trick to overcome this difficulty; he traces the vertebral column to paper, then cuts it out as a template for sculpting.
The centra are detailed to a final shape using
a high speed rotary tool.
Epoxy clay is then applied to the template to form each vertebral spine (i.e. the spike that rises vertically from each vertebrae). Once hardened, additional clay is applied to form each transverse process (i.e. the bits that stick out either side). This is a slow and tedious part of the sculpt.
If you have additional information, resources, images
or can help with translation of the Japanese descriptions
of this material I am very keen to hear from you.
Please contact me.