I’m trying to translate a text I’ve written where we explain forge and foundry but not in the literal blacksmithing sense. What is the appropriate word in Spanish?
a furnace or a shop with its furnace where metal is heated and wrought
a blacksmith's workshop; a smithy.
Since this seems to be both the workshop and the "oven" used for the smith's trade, I would translate as Fragua
f. Fogón en que se caldean los metales para forjarlos, avivando el fuego mediante una corriente horizontal de aire producida por un fuelle o por otro aparato análogo.
f. Taller donde está instalada la fragua.
See from the second definition that a fragua is the place (workshop) where the foundry is installed. My guess is that in this question's context1 that workshop would be the foundry. Now, it would not be a "foundry" in the literal sense, since you are not melting metal into a liquid, pouring it into a mold etc.
You could use in this context herrería for this "foundry" (which by description seems to be more like a smithy).
f. Taller en que se funde o forja y se labra el hierro en grueso.
f. Taller de herrero.
f. Tienda de herrero.
So, for the context give in the question I would translate
- forge as fragua (fragua as a furnance)
- foundry as herrería (to distinguish from the fragua/taller)
1 A foundry is a factory that produces metal castings.But I understand from the question that you want to change the "scope" of this place from "factory" to something more like "a few blacksmiths", meaning a smithy.