Chapter 8 Paints And Finishes
false. A HVLP spray gun is an internal mix gun.
The HVLP spray gun is an external mix gun. TRUE/FALSE
True
The Zahn cup is used to measure the viscosity of the primer or paint system. TRUE/FALSE
Primers, enamels, urethanes (polyurethane), and epoxies.
What are the common types of paint used on aircraft?
Dipping, brushing, and spraying.
What are three methods of applying paint?
A loose nozzle, clogged vent hole on the supply cup, or the packing may be leaking around the needle.
What could cause a pulsating or spitting fan pattern?
C
What could happen if the paint material is not properly mixed? a. fisheyes b. orange peel c. wrinkles
A
A rough surface that feels like sandpaper is an indication of? a. spray dust b. orange peel c. fisheyes
C
A spray gun that uses lower pressure and higher volumes of air is called a: a. HVLP spray gun b. Siphon feed gun c. Gravity feed gun
C
Aluminum‐pigment in dope is used primarily to a. provide a silver color b. aid in sealing out moisture from the fabric c. exclude sunlight from the fabric
A
Before spraying any finishing materials on unpainted clean aluminum, A) avoid touching the surface with bare hands. B) remove any conversion coating film. C) wipe the surface with avgas or kerosene.
True
Blushing is the dull milky haze that appears in a paint finish. TRUE/FALSE
True
Fresh air breathing systems should be used when spraying polyurethane paint because it contains isocyanides. TRUE/FALSE
True
Orange peel could be caused by not enough reducer or too little flash time between coats. TRUE/FALSE
True
Plastic Media Blasting (PMB) is an effective way of stripping paint of composite structures which causes less damage than sanding. TRUE/FALSE
B
The pressure used for a HVLP spray gun is __________ the pressure used for a traditional spray gun. a. lower than b. higher than c. equal to
C
The registration marks must be at least _____ inches high. A glider may display marks at least _____ inches. a. 8 inches, 4 inches b. 10 inches, 6 inches c. 12 inches, 3 inches
Acetone
This a fast-evaporating colorless solvent. It is used as an ingredient in paint, nail polish, and varnish removers. It is a strong solvent for most plastics and is ideal for thinning fiberglass resin, polyester resins, vinyl, and adhesives.
MEK
This also referred to as 2-Butanone, is a highly flammable, liquid solvent used in paint and varnish removers, paint and primer thinners, in surface coatings, adhesives, printing inks, as a catalyst for polyester resin hardening, and as an extraction medium for fats, oils, waxes, and resins.
Benezene
This is a highly flammable, colorless liquid with a sweet odor. It is a product used in some paint and varnish removers. It is an industrial solvent that is regulated by the Environmental Protection Agency (EPA) because it is an extremely toxic chemical compound when inhaled or absorbed through the skin. It has been identified as a Class A carcinogen known to cause various forms of cancer. It should be avoided for use as a common cleaning solvent for paint equipment and spray guns.
Alcohol
This is a slow-drying solvent that can be mixed with aircraft dope to retard drying of the dope film on humid days, thus preventing blushing
C
What could happen if the to be painted surface is not clean and free of any type of contaminants? a. The surface has the appearance of orange peel b. The surface feels rough c. Fisheyes could appear on the surface
Clouding or blooming of the film
What is a blushing paint finish?
C
What is likely to occur if HYDRATED wash primer is applied to unpainted aluminum and then about 30 to 40 minutes later a finish topcoat, when the humidity is low? A) A dull finish due to the topcoat ''sinking in'' to primer that is still too soft. B) Corrosion. C) A glossy, blush-free finish.
C
What is likely to occur if UNHYDRATED wash primer is applied to unpainted aluminum and then about 30 to 40 minutes later a finish topcoat, when the humidity is low? A) A glossy, blush-free finish. B) A dull finish due to the topcoat ``sinking in'' to primer that is still too soft. C) Corrosion.
Incorrect air pressure or the distance of the gun from the work is too large.
What is the cause for spray dust?
On the vertical tail surface or on the side of the fuselage behind the trailing edge of the wing.
What is the location of the registration mark on fixed wing aircraft?
To ensure that the surface is clean and free from any type of contamination.
What is the most effective way to eliminate fisheyes?
A
What is the usual cause of runs and sags in aircraft finishes? A) Material is being applied too fast. B) Too much material applied in one coat. C) Low atmospheric humidity.
Moisture in the air supply, adverse humidity, or changes in temperature.
What will cause a blushing paint finish?
C
Which defect in aircraft finishes may be caused by adverse humidity, drafts, or sudden changes in temperature? A) Orange peel. B) Pinholes. C) Blushing.
C
Which of the following are the desired effects of using Alodine on aluminum alloy? 1. A slightly rough surface. 2. Relieved surface stresses. 3. A smooth painting surface. 4. Increased corrosion resistance. A) 3 and 4. B) 1, 2, and 4. C) 1 and 4.
B
Which of the following is a hazard associated with sanding on fabric covered surfaces during the finishing process? A) Embedding of particles in the finish. B) Static electricity buildup. C) Overheating of the fabric/finish, especially with the use of power tools.
B
Which statement is true regarding paint system compatibility? A) Old type zinc chromate primer may not be used directly for touchup of bare metal surfaces. B) Old wash primer coats may be overcoated directly with epoxy finishes. C) Acrylic nitrocellulose lacquers may be used over old nitrocellulose finishes.
Methylene Chloride
e is a colorless, volatile liquid completely miscible with a variety of other solvents. It is widely used in paint strippers and as a cleaning agent/degreaser for metal parts. It has no flash point under normal use conditions and can be used to reduce the flammability of other substances.