I was able to find some old redprints for machine designs. The factory was designed to be mostly self sufficient, so I'm not actually sure what it will start producing beyond these. One thing I do know: the Factory possesses half the Spark of the sanctum (that's a lot), but each machine can only hold so much charge. They have to return periodically to restore their energy... but they're coordinated enough to "change shifts."
I'll update these records if we encounter any more machines.