Recoaters for powder-layer three-dimensional printers which are capable of producing enhanced powder layer uniformity and powder-layer three-dimensional printers having such recoaters are described. The recoater comprises a bridge, two supports, one at either end of the bridge, a powder reservoir, and a substantially rectangular plate which extends between the two supports and contains an opening through which the powder reservoir either extends into or through or through which build powder can be fed into the powder reservoir. The plate has a length to minimum width ratio of no more than about 7.0 and a length to maximum width ratio of no more than about 5.0, the plate being adapted to brace the bridge into a perpendicular relationship with the first and second supports when the recoater is being controllably moved and the powder reservoir is dispensing powder to form a powder layer.