Czech Aircraft CRUISER AIRCRAFT PS-28 Cruiser 2021, Руководство по обслуживанию

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PS-28 Cruiser
PS-28N Cruiser
CR-MM-1-0-00
CHAPTER 15 – AIRPLANE REPAIRS
Revision No.: - Date of issue: 2011-03-08
15 - 16
15.6.2.3 Application of primer (paint)
In order to reach a uniform resistance to corrosion and smooth surface, we recommend
carry out application by means of spraying (air standard gun with the upper vessel, air HVLP
gun, airless electric gun). The adjusting of the used gun (given by manufacturer) differs
according to the type - air pressure, jet diameter. Primer should be applied in several
sprayings (total thickness is not reached at a blow) with defined maximum dwell and total
drying time till further treatment or handling. Primer serves especially for anchoring
(adhesion to the substrate) the topcoats and can serve also for eliminating irregularities of
the surface (function of filer, for sanding). For surfaces from Al-alloys we recommend to use
the etch-primers for light metals based on alkyd or materials based on epoxy or
polyurethane (2-component paints); specific recommendations according to the table 15-6.
Surface
Manufacturer,
name
Type
Further
components
Surface
mass
Recomm. thickness
Drying (between
spraying / total)
18°C (65°F)
Al-alloys
BASF
Glasurit
801-1880
(base)
epoxy
BASF
Glasurit
965-35/2
(hardener)
Glasurit
965-50
(thinner)
1.6
[kg/mm/m
2
]
8.49
[ lb/in/sq.ft ]
0.025 mm ( 0.00098” )
(at 0.05 mm ( 0.00197” )
it can be also used as
filler)
15 min / 12 FH
epoxy –
fiberglass
PC (Lexan),
PMMA
(Plexiglass)
Tab. 15-5 : Recommended primers
15.6.2.4 Bonding
After total drying of basic coat we recommend to carry out total bonding of irregularities
including repairs of bonding. Recommended binders are shown in the table 15-5. After
drying perform sanding with emery paper with grain size of 240 until the surface is smooth.
After sanding clean dust and wipe of with grease remover and perform repairing paint coat
by primer (1/3 of coat thickness).
15.6.2.5 Application of top coat
In order to reach smooth surface we recommend again carry out the paint coat by spraying
(see 15.6.2.3).
Topcoat serves especially for creating the coat resistant to weather and external effects for
aesthetic rendering of the unit. Considering the higher loading by external effects we
recommend to use top materials, exclusively two-component ones, on the acrylic-
polyurethane or polyurethane basis, always with guaranteed adhesiveness to the used base
coat (according to manufacturer). It is possible to use to advantage some of the coat system
for car repairing. In our recommendation (see Tab. 15-7)
there are two types of colors: single coat (color shade and protection in one) double coat
(one-component color shade is formed by the substrate and protection is ensured by two-
component transparent top coat). By single coat paint it is possible to reach the wide
spectrum of colors, but it is difficult to do metallic paint coats (we do not recommend them).