Abstract: An apparatus for cleaning cotton having a frame which rotatably supports a cylinder member having a cylindrical surface supporting a fiber-engaging structure for seizing contaminated cotton. The frame supports a grid assembly which assists in the removal of undesirable particulates from contaminated cotton engaged to the fiber-engaging structure of the cylinder member. The grid assembly includes a plurality of grid bars connected to the frame in a spatial relationship such that any two contiguous grid bars are separated by a grid space. A shroud member is supported by the frame for controlling the loss of cotton fiber through the grid space between two contiguous grid bars. A method of controlling and/or reducing the loss of cotton during lint cleaning of contaminated cotton. A method for retrofitting a lint cleaner to modify the lint-cleaning ability of the lint cleaner.