Abstract: A device for preserving solder paste in the manufacturing of printed circuit board assemblies. In one embodiment, the preserving device has a frame adapted to be positioned on a stencil plate of a solder paste stenciling machine and a cover coupled to the frame. The frame has a wall that is configured to substantially surround at least a portion of the solder paste on the stencil plate between printing cycles. In a preferred embodiment, the wall is configured to surround a working region on the stencil plate defined by the area on the stencil plate that the solder paste contacts during a printing cycle. The cover is coupled to the frame to form a protective compartment that substantially houses the solder paste between printing cycles. As a result, the preserving device restricts the airflow across the solder paste to protect the solder paste from environmental elements within the stenciling machine.