After a branch is removed it is necessary to remove the stub which remains. These are removed with a knuckle or otherwise known as a spherical knob cutter which makes a precise cut and gouges out part of the stem so that callousing will not cause a swelling in this area. This is particularly the case with species where the scar tissue tends to bulge. Cuts made with a concave cut heals faster than straight cuts.
The spherical blades allow for the ideal combination of strength and precision, making for a clean "biting action" into the material. The cutting blades shaped like two halves of a sphere. This shapes allow it to cut aggressively into the wood so protruding stubs, or knobs, are quickly cut away, and then leaves wound that will heal flush with the branch or trunk for minimal scaring. In other words, this tool will create a hollow circular cut with one stroke that will enable the bonsai to heal quickly with minimum scarring.
Knuckle cutters may also be used as a finishing tool to remove root or trunk material in areas that are difficult to reach using other tools. However extreme care should be taken when using knuckle cutters on roots as they are not as sturdy as root cutters and can be damaged if you accidentally cut into a stone.
Another useful function of knuckle cutters is that they may be used to nibble away wood when carving deadwood.
As with all our Kaneshin tools, these large knuckle cutters are handmade by highly skilled Japanese craftsmen. Each tool is boxed and accompanied by a certificate of authenticity.
To cut safely without damaging the tool, the thickness of the branch you want to remove should be 1/3 - 1/2 of the size of the blade.