- ・comfortable and feels good when practicing keiko
- ・places a minimal burden on the feet of the student
- ・has a long usable life span
With these three points in mind, plywood type flooring which does not reduce the impact upon one’s feet will not be considered. Therefore, we will only consider natural wood flooring
Just having natural wooden flooring does not ensure that it is suitable for a kendo-jo. In selecting a wood species most suitable for kendo-jo flooring, we can only recommend one kind.
One of the first characteristics to look at is the “slide”. The ease or difficulty of sliding one’s feet across the floor in all directions needs to be just right. The feet cannot slide too easily nor too difficult to slide one’s feet across the floor.
In order for the kendo-jo floor to possess the appropriate sliding levels, the wood surface needs to have a certain amount of softness to it.
In Japan, decisions on kendo-jo flooring usually boil down to either hinoki (Japanese cypress) or sugi (Japanese cedar). However, when considering surface hardness, hinoki is harder than sugi and is therefore less desirable in this aspect.
Kendo master Hiromichi Nakayama similarly stated, “Hinoki is a very good material, but in winter, it becomes too slippery and breaks one’s form. To the degree possible, the material should be a solid board end to end of very old sugi of at least one “sun” in thickness. The material may be expensive, but it will last a very long time.” *Note: “sun” , pronounced “soon” is a traditional Japanese unit of length measuring 30.3mm (0.8382”).
The material should be mostly of the reddish heartwood. With larger portions of mixed white sapwood, unevenness tends to develop between the two. Similarly, if there are many knots present, unevenness will develop around the knots. Knots will also chip, split, partially or fully come out; requiring various procedures to fix the problem and result in unexpected repair costs.
From all of the above, the choice material is sugi, which Japan has in abundance. Sugi has few knots and its heartwood is red. We use natural Japanese sugi for our kendo-jo flooring.
We handle a variety of wood. We can also offer hinoki, pine and other species. For customers who desire a species other than sugi, we can help you. Please let us know your needs.