, soldering iron can be crafted with the following recipes

Autolearned
Player Recipe
Primary skill used: electronics(1)
Required skills: N/A
Time to complete: 20 minutes
Tools required:
> 1 tool with cutting quality of 1
> 1 tool with screw driving quality of 1
Components required:
> 2x electronic scrap OR 1x glow plug
> 1x copper OR 1x nail OR 1x wire
> 1x scrap metal
> 10x duct tape
> 5x copper wire
Byproducts:
(none)
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This recipe can be found in the following books when electronics is at least the required level:
What's a Transistor? (level 1)
Advanced Electronics (level 2)
AAA Guide (level 2)