Produces steel out of 2 unprocessed wood and 1 iron.
- Upgrading these are a low priority. Only upgrade if needed.
- Keep these 2-3 levels lower than your base.
- If your supply is full, but you need more ammo, don't be afraid to upgrade.
- Because it uses more wood than iron if your supply is low, it is more likely Harvesters that need to be upgraded.
- It is a good idea to keep these the same level as the rest of your industry, to keep ratios constant.
- don't forget to upgrade alongside sawmills to keep arrow production steady.
Characteristics at different levels
 original reference