A moulding process, in particular a bladder inflation moulding process for the production of a composite material based part, said composite material comprising a polymer matrix and reinforcing fibres, wherein at least a portion of external surface of said part is shaped by a corresponding interior surface of a mould. The interior surface of said mould is provided with a polishing. Chromium plating or nickel plating improves smoothness and glossy appearance. The best wave and relief appearance is obtained if the proportion of matrix polymer/reinforcing fibres is kept as low as possible. <IMAGE>