Fabrication of three dimensional objects with multiple operating modes

In a method of forming the body portion of a three-dimensional object from a polymerizable liquid by the process of continuous liquid interface printing, the process including advancing a carrier for the object away from a build surface while irradiating a build region between the carrier and build surface in a pattern of advancing and irradiating defined by an operating mode, with the body portion having a plurality of contiguous segments, the improvement comprising:

• changing at least one parameter of an operating mode at least once during the formation of said body portion for fabrication of different contiguous segments of said body portion, where said operating mode is:
• (i) continuous advancing with intermittent exposure;
• (ii) step-wise advancing with intermittent exposure;
• or (iii) reciprocal advancing with intermittent exposure.