Originally Posted by Pragma
Probably depends on your school and how active the faculty are about funding. It was uncommon for a student (including first years) NOT to have funding options during the summer in my program, but lots of faculty had external grants. However, these were never full time options (usually 10-25 hours per week depending on who you worked for).
This was the case for my program as well, although it was a fairly even split between RA/research/grant funding and money received either through the university clinic or clinical externships (one of the advantages of being just about the only accredited doctoral program in the state is that even during the summer, plenty of associated institutions were looking for cheap labor). But overall, just about everyone stuck around full-time during the summer; it was essentially an unspoken (or, depending on the advisor, repeatedly-voiced) expectation.
I also strongly encourage that all first-years follow paramour and Pragma's advice re: getting thesis stuff started up during that summer between the first and second years. If you've already finished your thesis, use that summer to get an independent research project off the ground.