Set NIC Priority

I currently have a computer that is attatched to 2 private networks. One is 10.x.x.x and one is 192.168.127.x. The Class C network is setup in our Machine shop so that the instructor here can send CNC files to the individual CNC machines. The Class A network is the School’s network where the instructor will be getting his e-mail, documents, internet, etc. The problem is that we distribute licensing from our server on the Class A network and the program will always look through the Class C network for them. How do I set these 2 NICs so that the one attached to the Class A network takes priority?