( composite crossbow can be crafted with the following recipes

Autolearned
Player Recipe
Primary skill used: fabrication(5)
Required skills: mechanics(3)
Time to complete: 0.15 turns
Tools required:
> 1 tool with cutting quality of 1
Components required:
> 5x heavy stick OR 3x plank
> 3x bone OR 3x human bone
> 1x long string OR 6x small string OR 12x withered plant OR 12x pile of straw OR 100x thread OR 100x sinew OR 100x plant fiber OR 100x yarn
Byproducts:
(none)
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This recipe can be found in the following books when fabrication is at least the required level:
The Bowyer's Buddy (level 5)
Zen and the Art of Archery (level 6)