Abstract: Apparatus for building a raw edge V-belt carcass comprising, a drum about which differing plies of material are wrapped and about which a cord is helically wound. A servicer adapted to supply rubberized fabric is located adjacent the drum. A squeegee adapted to apply a gummy film mounted on a fabric liner is located adjacent the drum and has an applicator roll engageable with a partially formed carcass on the drum. A cord winder mechanism has a head mounted adjacent the drum and has a motor-driven screw for causing the head to move along the length of the drum. The screw motor is tied to the drum motor at a ratio which is infinitely adjustable within limits to vary the pitch of the cord as it is wound on the drum. The cord winder has a mechanism for detecting changes in the tension on the cord and for using that information to cause variations in the speed of a cord let-off roll so that the speed of the cord let-off roll matches the demand caused by the speed of the drum.