A hemming and seaming machine (5) having a hemming conveyor (16) on which a workpiece is moved along a path of travel toward and through a hemming station which sews a hem in the workpiece is disclosed. The hemmed workpiece is then moved downstream to a folding station (25) where a spaced series of first air jets (61) selectively emit streams of air between a folding plate (26) and clamping plate (55) to create a vacuum therebetween to draw the leading edge of the workpiece off of the hemming conveyor and between the folding plate and the clamping plate. The leading edge of the workpiece is held between the clamping and folding plates while the workpiece continues to move along the path of travel. After a predetermined period of time has elapsed from the detection of the leading edge of the workpiece, or in response to the detection of the trailing edge of the workpiece, the leading edge of the workpiece is released from between the folding and clamping plates. The workpiece is then moved to a downstream seamer station (175), which sews a seam in the workpiece, and then to a downstream workpiece stacking station (177).