the platform 3 about a pin 5 a lifting abutment wall 6 located adjacent a travel limit position of the arm 4 and guiding members 7 for the pleated cloth 2 the platform 3 is particularly brought out in fig1 and 5 its shape is circular suitable for positioning pre shaped but not yet pleated fabric portions 8 and extends around a pin 5 which forms the pivot center for the arm 4 further the platform 3 is peculiarly pivotable about that same pin with a timed motion to that of the arm 4 more specifically the platform 3 is rotated step like concurrently with the forward movements of the arm 4 which is driven by a main cylinder 9 fig1 effective to reciprocatingly oscillate the arm 4 during the return movements of the arm 4 the platform 3 is held stationary advantageously it is the main cylinder 9 itself which controls both the reciprocation of the arm 4 and advancement movements of the platform 3 in fact and as shown in fig7 the arm 4 is terminated at the pin 5 with a plate 10 which is attached to a center pin 11 of the pin 5 connected to the platform 3 through a freewheel mechanism 12 for rotation in one direction only the freewheel mechanism 12 is made rigid with the platform 3 by means of a cup like extension 13 also shown in fig7 it should be.