Inputs are on the left side; the upper furnace array takes copper and coal, the lower one takes iron and coal. Replace all stone furnaces with steel ones as needed while playing.
Originally shared on the public FactorioPrints / Factorio School archive (factorioprints.com · factorio.school). Authorship preserved from the public catalog.
Inputs are on the left side; the upper furnace array takes copper and coal, the lower one takes iron and coal. Replace all stone furnaces with steel ones as needed while playing.