The method for the production of partial warps wound on warping beams or sectional beams, or warps of synthetic filament yarns wound on warp beams, which are completely stretched and sized, consists of sizing a group of parallel synthetic thermoplastic filament yarns, the filaments of which are not completely stretched, in a sizing zone, predrying the sized yarns in a heated predrying zone, subjecting the predried sized group of yarn by final drying in a heated final drying zone, and finally winding the dried group of yarns on warping or (sectional) beams, while the filaments of the filament yarns are stretched jointly and simultaneously in the predrying zone. The stretching occurs preferably between rolls (5, 6) assigned to the sizing zone and rolls (10) assigned to the final drying zone. The method may be carried out with conventional, at most slightly modified sizing machines and it furnishes very uniform partial warps or warps. In particular the filaments of the filament yarns are stretched very uniformly. In addition, a twisting or twist-replacement treatment of the filament yarns prior to sizing may be eliminated because warps are obtained, the filament yarns of which have sufficient cohesion for further processing and a high density of their filaments.