After passing through the pressure gauge, theammonia travels through a flowmeter. Theflowmeter is located on the front of the machine,which is within easy reach of the operator.With this meter, the operator is able to turn onor off the ammonia flow. Additionally, theoperator is able to adjust the flow obtaining max-imum development with a minimum amount ofammonia. Using this type of development system,the operator is able to turn the ammonia supplyon only when developing, thus savingammonia during warm-up and periods of idlingor nonuse.A water supply is used to aid in the distri-bution of the ammonia vapor within thedeveloping tank. Water is fed into the evaporatingdrip trays, creating additional vapor, whichincreases the ammonia’s effectiveness. This watersupply is controlled by a feed regulator (locatedon the front of the machine). Also the amountof water being supplied is visible through a tubeabove the feed regulator. Adjust the water flowto 60 drops per minute, and ensure that aconstant dripping of water is reaching themachine, or the drip trays may be damaged.COOLING AND EXHAUST SYSTEM.—Excessive amounts of heat or ammonia vaporsshould NOT reach the room in which the machineis located because of the installed exhaust andcooling system. The system consists of twinblowers, driven by a motor that exhausts fumesand hot air from the machine enclosure througha vent to the outside atmosphere. Therefore, apartial vacuum is created within the machinecovers, thereby causing air to flow into themachine rather than the counterflow that wouldotherwise exist. A blower time switch operatesthe blower motor independently of the restof the machine thereby ensuring the removalof vapors and hot air after the mercury-vaporlamp is turned off. The switch may be adjustedto operate for any given length of time up to30 minutes.MACHINE OPERATION.— A short warm-up period is required before material can befed into the machine. Always follow themanufacturer’s instructions during machineoperation. When starting the machine, make surethat the developer drain tube is inserted in theresidue bottle (fig. 3-64). Then, fill the storagetank with ammonia. If bubbles are encounteredin the feed system because of increasedtemperature or high altitude, dilute the ammoniawith cold water. Usually, a one-eighth to one-fourth dilution is sufficient.After the ammonia storage tank has beenfilled, turn on the main switch, and adjust theammonia feed to 50 to 60 drops per minute. Athigh speeds (30 ft per minute and above), the rateof drops per minute can be increased. On virtuallyall modern, large-size diazo machines, ammoniafeed is automatically increased and decreased tocorrespond with variation of machine speed.CAUTIONDuring machine operation, the ammoniafeed regulator should NEVER be turnedcompletely off. If the machine is leftrunning and no moisture is entering thedeveloper section, the evaporation tray andheater rods are likely to be warped becauseof excessive heat.After a short warm-up period, the machine isready for operation. The machine should be runfor approximately 20 min or until the operatingtemperature is between 180°F and 210°F. Timeand temperature may vary; therefore, alwaysfollow the manufacturer’s instructions. Feed thematerial into the machine with the original on top,adjusting the speed of the machine so that a clearprint is obtained.Printing speed is dependent on the trans-lucency of the original, the density of theopaque image, and type of sensitized materialused.Running the machine at speeds that are toofast will result in a background on the print.Running the machine too slowly will cause theimage to be weak or missing from the printaltogether. The only positive method forobtaining the correct speed for your machine isby running a test because each machine’s lightintensity changes with age.When stopping the machine, turn theammonia flow off, then feed a sheet of porouswrapping paper, 16 in. wide, into the machine.Stop the machine with the paper in positionaround the printing cylinder and between thesealing sleeve and the perforated tank. This willprevent the sleeve from sticking to the perforatedtank top and will also protect the belts from theheat of the cylinder while it is cooling.3-49
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business