The cutting blades of this 8 1/4" (210mm) Yoshiaki Carbon Steel Knob Cutter are shaped somewhat like two halves of a sphere coming together, which allows the tool to aggressively bite into wood while producing a cut that promotes healing.
Protruding stubs are easily and quickly nibbled away by the knob cutter in a controlled fashion. It can remove large amounts of wood quickly yet is precise enough to shape the final surface cut on the trunk or branch.
An additional use of the knob cutter is the removal of undesirable root or trunk material in the area of a partially removed tap root. The aggressive nibbling ability readily removes excess callous underneath the trunk where lack of space makes it difficult to use other tools.
The knob cutter is often used after the concave cutter. It's used to hollow out the cut after the concave has done it's job. Knob cutters are used by specialist. It's as versatile as other tools, however, there is not substitute.
The 8 1/4" Yoshiaki Carbon Steel Knob Cutter is the perfect combination of precision and power.
Yoshiaki Bonsai Tools are made the old fashion way - By hand, with some modern machinery. The machine forms the edges outline, then humans finish the edges, assemble and finish the product. The craftsmanship and cutting performance of Yoshiaki tools is superior and why bonsai enthusiast prefer this brand.