Systems methods and devices for packaging used grain bags as the grain bags are being unloaded. The system is located at the top of a grain unloader machine or a grain extractor machine. The invention uses a pair of plates with retractable winding cores placed at the center of each plate. At the start of the unloading process, the end of a grain bag is attached to both the retractable winding cores. As the grain bag is unloaded, the unloader moves down the length of the grain bag. The portion of the grain bag that is emptied is rolled up by the rotating winding cores. The winding cores are powered by one or two external motors controlled by a user. Once the empty grain bag has been completely rolled up, the retractable winding cores can be retracted.
