American cinematographer (Jan-Dec 1945)

An All -Friction Drive For Developing Machines By W. G. C MOTION picture developing ma¬ chines designed on a friction drive principle that for all prac¬ tical purposes eliminates film breakage and damage from mechanical causes, has brought an enviable reputation and world-wide business to the manufacturer, The Fonda Machinery Company of Holly¬ wood. . BOSCO This company, which has been in pro¬ duction for nine years, has perfected an entire drive on film-carrying rollers with the power applied directly to the outer and upper edges, but which only applies when there is normal tension on the film. This unique driving action is achieved by creating a light constant drag or tension on the film all through the machine, with ■ ■ |j ' ** I U I t; C <T ||| m i 4 ; || J Top left: this Fonda developing machine has a capacity of 35 ft. per minute with a 3-minute develop¬ ing time for positive. The all-stainless steel construc¬ tion is standard. Bottom left: here is the same installation with the electrically operated hoist fully extended for ease and simplicity of servicing and cleaning. the resultant tension being relieved in the following manner: the film-carrying rollers are mounted on a shafting which is mounted yieldably downward on sad¬ dles carried on springs, and when the film drag, or tension, exceeds the amount determined by the spring adjustment these upper film-carrying rollers are drawn downward and away from the driving rollers until sufficient slack is fed up to relieve the tension, which then per¬ mits the spring to draw the film-carry¬ ing rollers into contact again with the driving rollers. This drawing downward action takes place almost constantly throughout the machine, but is notice¬ able only in the dry box where film shrinkage is added to the drag set up in the machine. On the take-off end the friction roller keeps the tension constant to the rewind. At the first entrance of the film into the machine a speed is established which remains constant throughout the develop¬ ing and drying process unless changed by the operator. The driving rollers are directly over the upper film-carrying rollers, and all driving mechanism is out of tanks and solutions. The upper film-carrying rollers are mounted so that they may engage or disengage the driving rollers automati¬ cally. All film-carrying rollers in the wet end are mounted individually free, and in turn are all mounted on free-turning tubing or shafting. All film-carrying rollers in the drive-box, in addition to be¬ ing individually free, are mounted on tubing which in turn is mounted with ball-bearings on shafting, the entire unit being free to rotate or to slide laterally on the shaft, thus becoming self-align¬ ing. At no place does the film pass over a tight roller. With the Fonda system there are no sprockets to pull or tear the film, and no elevators are necessary to regulate tension. Speed and safety cooperate in¬ stead of limit each other, and the ten¬ sion of the film remains virtually con¬ stant throughout the machine. Built to specifications for any film capacity, and with a wide range of speeds, Fonda developing machines are built to both 35mm or 16mm standards; or, equipped with rollers that handle both film sizes. The same machine will process one or the other without the necessity of making mechanical changes. These machines are proving them¬ selves not only in the major Hollywood labs of Consolidated and Technicolor, but also in places like India and the Egyp¬ tian Sudan where the most adverse con¬ ditions of water temperature and humid¬ ity exist — conditions specifically designed (Continued on Page 132)