I've been working on my Master's part time while working as a full time engineer. My company is paying for the classes. I've decided I'd like to continue my education and pursue the PhD. I could quit and be a full time grad student, but I don't really want to take the pay cut and lose all the benefits I receive right now. The other option is to continue taking classes part time and spend 6-8 years working on the degree that would otherwise take 4. Most of the classes are offered at night so there wouldn't be much of a conflict with regards to that. By the time I get around to my dissertation it may be necessary to focus on that full time.
My degree would be in either Industrial Engineering or Operations Research so the real world work experience is necessary. Most of the research that is going on in the department is related to ergonomics, cost valuation, quality management, production systems, etc. Would I gain more making minimum wage assisting in one of these labs or making an engineer's salary applying these principles in an actual manufacturing environment? I know part of earning a PhD is training a way of thinking and I wouldn't want to lose out on that. A shitty dissertation would also not do much for me if I don't have adequate time to work on it.
Right now I'm thinking about continuing with taking 2 classes a semester for 3 years (for a full time student this would be 3 classes a semester for 2 years) and then quitting and finishing the dissertation as a full time student. Anyone tried this before?