NOTE: Damage, which does not exceed 0.003 inch (0,0762 mm) in depth, is considered minor surface damage. Removal of entire damaged area or polishing repaired area is unnecessary. Pitting to a maximum depth of 0.003 inch (0,0762 mm) is acceptable.
(1)
Remove high spots of damaged surface by polishing with an Arkansas polishing stone (SECTION VII) of suitable size and shape.
(2)
Break all sharp edges.
9. Repainting Parts
A. Method No. 409A: Alloy Part Painted Surface (Enamel) Repair
Repair painted surfaces of alloy parts, using enamel, as follows:
NOTE: Heat discoloration due to normal service temperature is not objectionable; however, scale that may come loose shall be removed by brushing while cleaning.
(1)
Thoroughly clean part to be painted. (Refer to SECTION II.)
(2)
After cleaning, blend and polish raised edges formed by nicks, gouges, burrs, and scratches. Feather abraded paint and bare metal smoothly using abrasive cloth (Federal Specification P-C-451) (SECTION VII) as required.
(3)
Touch up exposed bare metal with aluminum touch-up solution (Method No. 402E).
(4)
Apply primer as specified in applicable manual to all surfaces that require painting, except machined interfaces and threads.
(5)
Apply enamel as specified in applicable manual to all surfaces that required painting, except machined interfaces and threads.
NOTE: Shade new coating of enamel into adjacent painted surface.
Repair Page 443 Apr 1/05
20-00-02/70-00-01
B. Method No. 409B: Alloy Part Painted Surface (Color-coat) Repair
Repaint surfaces, using color-coat (SECTION VII), as follows:
(1) Prepare surface to be painted.
WARNING: SOLVENT VAPORS ARE TOXIC AND FLAMMABLE. DO NOT INHALE VAPORS. OBSERVE FIRE PRECAUTIONS.
(a)
Dip the part in paint and carbon remover (SECTION VII). Where complete stripping is not desirable or feasible, brush-on paint remover (Federal Specification TT-R-251) (SECTION VII) may be used.
(b)
Thoroughly clean, wipe, and dry the part. (Refer to SECTION II.)
(c)
Magnesium parts from which the paint has been removed in preparation for repainting shall be treated to prevent corrosion as described in SECTION II.
(2) Repaint external and non-critical surfaces of parts, unless otherwise specified in applicable manual for unit in work.
(a)
Plug all holes and mask all areas not to be painted.
(b)
Apply one coat of primer (Method No. 402J) and allow to air-dry 15 to 30 minutes followed by one hour at 175 to 225F (79 to 107C), then apply one coat of color-coat (color as specified in applicable manual) (Method No. 402K). Allow air-drying 15 to 30 minutes followed by one hour at 175 to 225F (79 to 107C).
10. Repairing Riveted Parts
A. Method No. 410A: Damaged Rivet Replacement General Guidelines
Damaged rivet replacement should be performed in accordance with the following general guidelines:
(1)
Rivets shall be formed by the cold continuous squeeze method. In this method, riveting machines, rivet sets, and rivet set adapters, specified in applicable manual, are used to form the rivet head from a continuous squeezing operation.
(2)
The proper replacement rivet for an assembly is listed in the illustrated parts list of applicable manual.
(3)
Rivets are manufactured in various shapes and sizes. Figure 405 shows two kinds of manufactured rivet heads; protruding (round) and 100-degree flush. It also shows two ways of upsetting rivets.
(4)
Manufactured head is the head produced at the time the rivet is manufactured and before the rivet is installed in an assembly.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：标准施工手册 STANDARD PRACTICES MANUAL 20-00-02/70-00-01(85)
