It is imperative to meet regularly with the chair of the dissertation committee, for support and guidance, and to ensure that you are pursuing a productive line of inquiry. Researching and writing the doctoral thesis should not take more than 2-3 years. Anything beyond that is considered beyond "normative time."
The Center for Academic Skills Enrichment (CASE) has staff to assist graduate students with the writing of their theses. The Graduate Division gives guidelines on the final format of the thesis. (It is especially important to verify required margins). For details, consult the Guide to Filing Theses and Dissertations at UCSB, available on the Graduate Division website. You may file your dissertation during a quarter when you are not a registered student, but to do so you must pay a filing fee equal to one-half of the registration fee and must be on an approved official Filing Fee Leave of Absence. In order to be on an official Filing Fee Leave of Absence the student must be registered the quarter prior to filing.
Candidates may continue to work as Teaching Assistants while writing their dissertation as long as adequate progress is being made. There are, however, certain limits set by the university on the number of quarters a student may hold a TA-ship: 12 quarters; 15 quarters may be granted by the Faculty Graduate Advisor; the Dean of the Graduate Division may grant 3 additional quarters. However, there is no exception to the maximum 18-quarter rule.