An improved version of composite layer manufacturing (CLM) has been invented. CLM is a type of solid freeform fabrication (SFF) — an automated process in which a three-dimensional object is built up, point-by-point, through extrusion of a matrix/fiber composite-material precursor. The elements of SFF include (1) preparing a matrix resin in a form in which it will solidify subsequently, (2) mixing fibers and matrix material to form a continuous preimpregnated tow (also called “towpreg”), and (3) dispensing the towpreg from a nozzle onto a base while moving the nozzle to form the dispensed material into a series of patterned layers of controlled thickness.