Aircraft Finishes Flashcards
Name the safety and health precautions to be observed in operating a dope room including storage of material.
The room should be well-lit, and ventilated using spark-proof electrical equipment. All flammable material is to be stored in fireproof containers in protected areas. The room should be located in a separate building or isolated by metal partitions and fireproof doors.
What type of test can be performed to identify existing paint finishes?
Engine oil will soften nitrocellulose, but have no effect on epoxy or acrylic. MEK will pick up pigment from acrylic but not epoxy.
What causes blushing when applying dope or lacquer and how can it be prevented?
Blushing is caused by excessive humidity during the application process. Rapid evaporation of solvents and thinners cools the surface, causing condensation. Blushing can be eliminated by heating the room, use of dehumidifiers, or by use of a blush-retarding thinner that increases drying time.
What is the purpose of using fungicidal dope when finishing aircraft fabric?
The prevent micro-biological deterioration (rotting) of the fabric.
What are the identification marking requirements for US registered fixed wing aircraft?
Roman capital “N” followed by registration number. Must appear on both sides of fuselage or vertical stabilizer. All characters equal in height 12” or greater, 2/3 of height in width. Exceptions are the number “1” at 1/6 of height and “M” and “W” with same wide as height. Width of character lines are 1/6 of height and spacing between characters is 1/6 of character height.
What are two types of dope used for aircraft finishes?
Nitrate and Butyrate.
What is the advantage of Butyrate over Nitrate?
Less flammable.
What would happen if dope was ever used over paint or enamel?
It would lift and remove the paint or enamel.
What is applied to metallic surfaces as a common resistant covering before the application of enamel or lacquer?
Zinc Chromate primer.
What are the most common methods of applying aircraft finishes?
Dipping, brushing, or spraying.
What type of paint be used over any paint system that is in good condition?
Epoxy topcoats, general touch-up, or touch-ups on defects in baked enamel coatings.
What is normally the cause of runs and sags in a spray paint finish?
Too much paint, either by holding the gun too long in one position or by holding the gun too close to the surface.
What causes an “orange peel” or “pebble” finish?
Spray gun setting, incorrect air pressure, incorrect paint viscosity, or holding gun too far from surface.
What is used to thin Chromate primer?
Toluene.
Which federal regulation prescribes the size and location requirements for aircraft identification numbers?
FAR Part 45
