A New Roll-Film Dryer

Abstract

Roll film has become an established feature of serial roentgenography (1–3). Developing, fixing, and washing have been relatively simple with the Fairchild-Smith motor-driven x-ray roll-film processing unit. Drying, however, because of the length of the film, up to 75 feet, has been difficult, requiring careful hanging and separation to prevent sticking (4). Standard hot-air dryers are ill suited for this purpose because of the long time required for the drying, and the necessity of draping and looping of the roll film, demanding constant attention to prevent scratching and falling. Recently, a new drying apparatus has been made available.2 Mechanism of Dryer Parts: The dryer is sturdily constructed of stainless steel and built to process films of varying widths up to 12 inches. Essentially, it is of simple design, consisting of four main parts: a 1/3-horse-power, 60-cycle, 115-volt motor; a spring-type 60-minute timer; three 15-ampere coil heater units; and two fans. The motor has a dual purpose: it provides, through a gear arrangement, transport of the film and furnishes the power for the twin fans. The blowers are arranged on either side, and a baffle forces jets of warmed air to circulate on both sides of the film. Hot air is generated by the three heating units located at the bottom of the dryer. The timer can be pre-set for the estimated drying period and automatically shuts the unit off. Operation: The operation is simple. The Fairchild-Smith processing x-ray roll film developing device is attached to the dryer (Fig. 1). The “leader edge” is detached from the reel and is drawn by hand into the drying chamber. The dryer is then turned “on.” The loading strip is allowed to dry, which usually takes half a minute. It is then attached to the “take-up” spool with a strip of adhesive (Fig. 2). The timer is set according to the length of film to be dried. For a full 75-foot roll at a speed of 22 inches per minute, the drying time is fifty minutes. In case of excessive humidity, the speed of film transport may be slowed. There are four speeds, with a maximum of 22 inches per minute. Adjustment to the desired rate of film transport may be had by pre-setting the lever drive at the clutch. Discussion The roll-film dryer herein described has had constant use during the past year. A total of 150 rolls of film of approximately 75 feet each have been processed. Film varying from 9 1/2 to 12 inches has been used without mechanical difficulties. Because of the compactness of the unit (25 × 25 × 20 inches), it occupies only a small corner of the dark room. Considerable time has been saved in the actual film drying period and, more important, the automatic feature obviates the need of attention. In no instance was there failure to secure a dry, finished, and unmarred product. Summary and Conclusion A new automatic roll-film dryer is here described.