Part 4 of an International Correspondence Schools instruction paper on silk throwing, continuing the treatment of hard-silk winding. It describes winder variations (fixed-hanger, variable-speed, drum take-up and double-deck winders), variable-speed transmissions, and the winder operative's work: beating out skeins, placing skeins on swifts, removing lacing strings, starting and tying ends, and doffing bobbins. It also covers bobbin boards, power, cleaning and oiling, defective bobbins (tight, hard, soft, ridgy, lapped, scratched), speed and production calculations, and ends with examination questions.