It might be impossible for others to build such money burning machines but not for Simon. After all, where was this place? This place was inside the dungeon that was created by him.
A dungeon is a place filled with riches ad unknown dangers according to adventurers; However, Simon disagreed. A dungeon was not some ordinary place but a special dimensional realm that can only be created by the demons.
It has its own laws and rules and is separate from the world outside which makes it a pretty special place. For a demon Noble, a dungeon is just like an extension of themselves and reflects its master.
Based on it, a dungeon can both become a place filled with riches or extreme dangers at every point. Anyways, the point is, as long as he keeps on growing the dungeon, it won't be long in the future when his dungeon will be able to produce all those materials required to manufacture the Andromedas on its own.
If you are also a mecha loving fan, vote for the book with Golden Tickets and Power Stones. Don't forget to leave a review if you like the book.