Abstract: In a layboy arrangement to which are delivered simultaneously side-by-side sheets to form a plurality of piles of such sheets edge joggers are provided to align the outside edges of the piles of sheets and a mechanism is provided which operates to align the adjacent edges of adjacent piles. The mechanism is in the form of a chain guide bar or plate around which an endless link chain is driven and from which project a set of overlapping leaves. The apparatus is mounted such that the overlapping leaves on the bottom edge of the chain bar project between the piles of sheets. The chain is driven to move the leaves around the periphery of the chain bar such that an active surface moves in the direction of travel between the sheets as they are edge jogged into their even edge piles on opposite sides of the overlapping leaves of the guide mechanism.