Method for building a cotton module on a mobile cotton harvester

A method for forming a cotton module on a mobile cotton harvester, including the steps of:(a) removing cotton from cotton plants as the harvester is moved across a cotton field;(b) conveying the removed cotton into a cotton receiver structure including a plurality of surfaces of known extent defining and substantially enclosing an interior space;(c) distributing the cotton in the cotton receiver structure substantially evenly with respect to a selected one of the surfaces of the receiver structure; and(d) periodically compacting the cotton in the cotton receiver structure substantially evenly against the selected one of the surfaces by forceably moving a compacting element having an extent only marginally smaller than the extent of the selected one of the surfaces against the distributed cotton and toward the selected one of the surfaces.