Raft techniques in three-dimensional printing

A computer program product for operating a three-dimensional printer comprising non-transitory computer executable code embodied in a non-transitory computer-readable medium that, when executing on one or more computing devices, performs the steps of:

• determining a processing height for depositing each of a plurality of layers in a three-dimensional print;
• fabricating a base layer of a raft for an object in the three-dimensional print;
• fabricating a plurality of intermediate layers of the raft on the base layer, wherein each of the plurality of intermediate layers is deposited according to a pattern that is rotationally offset from that of an immediately adjacent intermediate layer by about sixty degrees;
• fabricating a first layer on the plurality of intermediate layers to form a top layer of the raft, the first layer fabricated at a distance from an underlying intermediate layer no greater than the processing height;
• fabricating a second layer of the three-dimensional print on the top layer of the raft with an exit port of an extruder at a first height to form an initial layer of the object, wherein the second layer is extruded at a distance from a top of the first layer greater than the processing height, thereby forming a relatively weak bond between the first layer and the second layer;
• and
• fabricating a third layer of the three-dimensional print to form a subsequent layer of the object on the initial layer of the object, wherein the third layer is extruded at a distance no greater than the processing height from a top of the second layer such that the extruder is closer to the second layer when forming the third layer than the extruder was to the first layer when forming the second layer, thereby forming a relatively strong bond between the second layer and the third layer.