obtained then the pneumatic cylinders 19 and 20 are activated causing the advancement of the bar 18 until the edges of the wings 18 a and 18 b that delimit the gap 18 c abut against the profiled elements 17 a and 17 b thus locking the length of textile material 2 once the length of material 2 has been clamped the electric motor 16 is activated and causes the advancement of the carriage 11 and therefore of the cutting assembly mounted thereon in this manner the rotating blade 13 by advancing along the gaps 17 c and 18 c transversely to the unwinding direction a cuts from the length of textile material 2 a piece 33 whose longitudinal dimension is equal to the longitudinal dimension between the edge 31 and the gap 18 the operating cycle is then repeated in the manner described above it is evident that the described apparatus allows to work on individual pieces obtained from a continuous length of textile material wound on a roll this ensures that the various layers that compose the piece once the cutting of the length of material has been completed cannot arrange themselves out of place during the handling to which they are subjected in order to be prepared for successive treatments such as bordering quilting and so forth if the tubular part is constituted by a tubular article the stitched seam closes the leading edge and forms a pouch that can be used to cover mattresses or the like in the practical embodiment of the invention numerous modifications and variations are possible all within the scope of the same inventive concept in a second embodiment of the invention the tabs 22 for elastic retention of the margin 23 of the.