(b)
Make a frame, approximately 3/8-inch wide by 1/2-inch high, around the clean surface.
NOTE: Use wood, clay, or high temperature vacuum sealant tape
____
for the frame.
(c) Apply a thin layer of prepared silicone rubber on the textured surface in the frame with a brush. Continue to use the brush until you cannot see air bubbles.
NOTE: Almost all brands, types, or colors of castable silicone
____ rubber are satisfactory, but not the dark red types which contain finely divided iron oxide. Dow Corning Silastic RTV "B", "E", 587, or 93072, and General Electric RTV41 or RTV61 are prefered. Obey the manufacturer's instructions when you prepare and use these materials.
(d) Pour the remaining silicone rubber on the brushed surface until it is 1/4 inch thick. Let it cure at room temperature for 48 hours.
NOTE: One pound of prepared silicone rubber will make a
____ 10-inch-by-10-inch-by-1/4-inch replica.
(e) When the silicone embossing pad is dry, remove it from the surface.
S 498-017
(4) Put the silicone embossing pad over the hole on the decorative face of the panel.
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S 498-018
(5) Hold the silicone embossing pad in position with weights or a vacuum bag.
NOTE: In areas where you cannot use a silicone embossing pad,
____
seal the hole with masking tape.
S 348-070
WARNING: DO NOT GET SCOTCHCAST 5126 ADHESIVE IN YOUR MOUTH OR EYES, OR
_______ ON YOUR SKIN. DO NOT BREATHE THE FUMES. PUT ON A PROTECTIVE SPLASH GOGGLE AND GLOVES. SCOTCHCAST 5126 ADHESIVE CONTAINS EPOXY RESINS WHICH CAN CAUSE INJURY TO PERSONS.
(6)
Fill the hole, from the nondecorative side of the panel, with Scotchcast 5126 adhesive.
S 348-021
(7)
Let the adhesive cure at room temperature for 24 hours, or at 140°F for 2 hours.
S 098-022
(8)
Remove the silicone embossing pad or the tape.
S 378-023
(9)
Apply silk screen ink of the correct color.
S 378-024
(10)
Let the silk screen ink dry for 15 minutes.
S 498-025
(11)
Apply the silicone embossing pad to the repaired surface, if it is possible. Then, apply vacuum pressure (approximately 10 inches of Hg).
S 098-026
(12)
Let the surface cure for 15 minutes at 160°F before you remove the embossing pad.
TASK 25-00-00-308-023
6. Repair Tedlar Covers of Aluminum Laminates
__________________________________________
A. General
(1) To repair scratches or small dents (not more than 0.050-inch depth), do the repair procedures given for crushed core panels.
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7. Repair Perforated Panels
________________________
A. General
(1) These paragraphs give instructions to do the repairs (not more than
1.5 inches in diameter) that follow:
(a)
A repair of acoustical panels that have damage through the decorative surface and fiberglass screen
(b)
To apply tedlar laminate to the surface of the acoustical panels.
B. Standard Tools and Equipment
(1) Brush - Hand, to apply mixed adhesive
C. Consumable Materials
(1)
Adhesives
(a)
A00039 Epibond 126
(b)
A00040 Furane Hardener 9812
(c)
A00153 BMS 5-30
(2) 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：747-400 AMM 飞机维护手册 EQUIPMENT/FURNISHINGS 1(16)
