Abstract: A U-turn high capacity sheet feeder including: a sheet storing tray for holding a stack of sheets of paper, having a stack advancing spring for advancing a stack of sheets of paper; a transfer roll; a feed roll and a drive mechanism controlled to separate an individual sheet of paper from the sheet storing tray to the transfer roll for allowing it to be further driven by the transfer roll to a host machine; a U-turn baffle channel for guiding an individual sheet of paper moving away from the sheet storing tray to the transfer roll; a pivotable baffle channel for guiding an individual sheet of paper from the U-turn baffle channel to the host machine and for supporting the individual sheet of paper against the feed roll of the host machine; a control mechanism for determining the timings of the engagement of the feed roll and the drive mechanism for transporting individual sheets of paper one by one into the feed zone of the host machine in conjunction with feeding cycle of the host machine; and a housing, whic