/ bokken can be crafted with the following recipes

Player Recipe
Primary skill used: fabrication(7)
Required skills: N/A
Time to complete: 300 minutes
Tools required:
> 1 tool with wood sawing quality of 1
> 1 tool with cutting quality of 1
Components required:
> 1x log
> 16x vegetable cooking oil OR 16x animal cooking oil OR 250x lamp oil OR 250x motor oil OR 2x tainted tallow OR 2x tallow OR 2x mutant tallow OR 2x human tallow OR 2x mutant humanoid tallow
> 2x fur pelt OR 2x leather patch
> 20x duct tape OR 20x thread OR 20x sinew OR 20x plant fiber OR 20x yarn
Byproducts:
> 30x splintered wood
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This recipe can be found in the following books when fabrication is at least the required level:
The Swords of the Samurai (level 6)