I wanted to craft one of the chain links in the Great Furnace but it requires a chain mold. then I looked in the casting table but there is no recipe for it. so then I unlocked the knowledge for chains. by doing that the chain mold is listed crafted at the blacksmith's bench. but there is nothing on the blacksmith's bench. am I missing something?

In the middle of writing this, I figured out the issue.

"Solution"
I was trying to find it on the garrison blacksmith bench. But after placing a regular blacksmith binge everything is there.

"Suggestion"
Perhaps it would be a good idea to add the recipes to all related blacksmith bench upgrades.

Honestly, this mod should be an official expansion of the game, love the work.