On April 6th 2013, I attended a bone tool making workshop with Jim Croft. The workshop was hosted by the Guild of Book Workers—Delaware Valley Chapter and was located at the University of Arts in downtown Philadelphia. Jim had driven from his home in Idaho with his car loaded up with bones and tools. He had brought many of his tools which he made in numerous shapes out of deer, elk, yak, or moose bones.
The age and type of animal are important considerations when making bone tools. Generally, one wants to select a bone with low porosity. These generally come from older animals that live in the wild; however, many of the commercial bone tools are made from domesticated cow, whose relatively inactive lifestyle does not allow for the formation of dense bones. For the workshop, we had the choice of working with deer, elk, or yak. Leg and rib bones are large enough to make useful tools for bookbinding. Jim had pretreated the bones by slow-cooking them over three days to remove the marrow. For more flexible tools, rib bones are preferred because they are built to allow movement during the life of the animal. Once the bone is selected, the first step is to roughly hew the general shape with an ax. The more exact one can be with the shaping, the less filing work will be needed later.
For my project, I choose a deer bone from the lower leg. I wanted to make a bone tool that fit my hand and came to a point. This shape is useful for scoring and lifting paper. The bone needed to be larger than the final product to allow for significant loss during the carving process.
After the general shape was hewn, successive grades of files were used to modify the form. Large files were attached to the tables, and I had to stand and use my bodyweight to work the bone smooth. Some people wore masks because the process threw a lot of bone dust into the air.
The shape was further refined with finer and finer files. The final smoothing and polishing was done with sandpaper until the surface was perfectly smooth with an almost satiny texture. It took me more than four hours to make one tool! I really gained an appreciation for the time and effort required to make these beautiful tools.
Jim Croft frequently gives workshops all over the country and I would highly recommend taking a class with him if you have the opportunity.