of the conical rollers 3 4 spaced apart from one another in series along the travel path p of the strip or sheet s of prepreg material the serially arranged pairs of rollers therefore progressively impart an increasing degree of curvature to the prepreg strip s as it progresses through the apparatus 1 on the travel path p also supported on the frame structure 8 and arranged distributed along the travel path p between the respective pairs of rollers 3 4 are three heating devices 11 e g radiant heaters for heating the strip s as it travels through the apparatus 1 in this regard the heating devices 11 soften the polymer matrix of the prepreg material rendering the strip or slat s less stiff and more easily workable between the conical rollers 3 4 as an alternative to using one or more individual heating devices 11 for discrete application of localised heat to the strip s it will be appreciated that the apparatus 1 of the invention could be installed in a chamber or room having one or more heating unit for a controlled ambient temperature although specific embodiments of the invention have been illustrated and described herein it will be appreciated by those of ordinary skill in the art that a variety of alternate.