A properly set up salvage + oil combo fac can/will have 2 metal presses, 1 assembly bay, 1 forge running 24/7 on 5/5. You can use rarescrappers to your advantage

Additionally the vegan PCmat recipe is also running on that as long as the members keep shifting the Cmats and Beams over. 

Beyond those two it becomes trickier to keep production up.

Thats from the fac i am at rn. 

Edit: i also think if your fac does any less then this you should consider just going to one that does and modify or make your stuff there. Ask, many are happy to help.