I fully agree with the two previous replies. If you're in it for the academic career track, it's always best to do it now. The chances you'll want to come back and go through the application process all over again after getting a nice paycheck for a year are really, really slim. Even with friends I know who worked and really, really saved during their time off, they resented seeing those savings dwindle down so quickly as soon as they returned to school, and the experience was never the same for them, in my opinion. I know the fear of paying back student loans is daunting, I agree with that too. But if you ask around and look at the university's website, and find there are at least some chances you'll get funded at least part of time, even if they are in different/related disciplines and maybe even only guaranteed a quarter at a time--then that will lower the amount you'll have to take out in loans. Plus, I've found that applying for RA and TA positions really gets to be a skill well learned...after the first couple of tries you get to be a whiz at it even if you don't get it at first. Also, most faculty find that type of initiative impressive, so your advisors have a better shot at advocating for your funding the time around...i.e. "This student has made substantial progress in the program even without our funding, and was actively pursuing funding outside the department, and this demonstrates extreme initiative and promise of success in our program so should be ranked high in our funding priorities"
Best of luck to you.