a roller cotton gin including a ginning roller and a stationary knife to which seed cotton is conveyed by the friction surface of the ginning roller for separating lint fibers from the cotton seed , and a rotary stripping blade device adjacent the stationary knife formed from a square cross section bar having v - shaped grooves axially spanning each face adjacent the corners providing blade formations for advancing the seed cotton deposited on the surface of the ginning roller to the zone of the stationary knife . the seed cotton is received in and advanced by the channel - like spaces between successive blade formations , and the stripping blade device has a diameter which is a small fraction of the ginning roller diameter and rotates at a speed causing the surface speed of the blade edges to approximately the same as the surface speed of the ginning roller such as to restrain seeds in the channel - like spaces during seed advancement over the pinch point at the edge of the stationary knife to a release point while the ginning roller strips lint from the restrained seeds and then releasing the seeds from blade restraint at the release point after they travel about 1 / 2 the staple length beyond the pinch point to return any incompletely ginned seeds still having attached fiber to the knife edge before the next blade applies advancing force to the seed and thereby withdraw substantially all the fibers from the seed . flexible strip - like pads provided in the channel - like spaces to press the seed cotton against the ginning roller surface , and an auxiliary feed control roller and an unginned seed restraining and recycling comb structure are also disclosed .