Es una buena pregunta. La verdad es que con cepillos no tengo experiencia, pero te puedo pegar este extracto de fine-tools, en el que habla del problema que tienen de traer hachas desde Japón a Alemania. Como en Europa el clima es más seco, le cogen holgura los cabos:
With our experience with the very different climate conditions between Japan and Central Europe, we needed to find a solution for problems we have experienced with Japanese hafted tools. In Japan, the air is always very humid, but in Europe rather drier. So when a haft is finish-fitted to an axe in Japan, and then stored by us here in Germany, it is possible that the haft will dry out and loosen up in the head, and in use the head can then fly off the haft. So originally we have arranged with the manufacturer that these tools are shipped to us with the haft only provisionally fitted to the head and the wedge only slightly inserted. But sometimes customers had the problem to disassemble this provisionally fitting. So now we are in the process to change to ship them unfitted. This will be a rolling change and therefore you will find a notice with the product description whether the specific item will be shipped provisionally fitted or unfitted. The user must finish the fitting of the haft and attachment of the head! This is best done after letting the wood acclimatize at least a week to the area where the axe will be stored and used. To fit the haft to the head, the shape of the end must be slightly reworked to fit into the hole in the axe head. For an exact fit, as much as one or two inches may need to be removed to completely fill the hole, or eye, in the head. We currently have a few axes in our store room that feature unfitted raw haft blanks.
Sacado de Japanese Hatchets and Axes | FINE TOOLS