E. Prepare the cargo lining.
NOTE:____The damaged area on the cargo lining must be smooth. If it is not smooth, the patch or doubler will not bond correctly to the cargo lining.
S 028-013
(1)
Remove the cargo lining from the support structure if it is
necessary (Ref 25-59-01/401).
S 348-014
(2)
Remove the loose fibers of the glass fabric laminations around the edges of cracks, tears, and holes in the lining.
NOTE: A sharp knife or scissors can be used to remove the loose
____ fibers. The loose fibers can prevent the patch or doubler to bond correctly to the cargo lining.
S 348-015
(3) Cut away the damaged area where you see separation in the layers of the glass fabric laminations.
NOTE: The hole you cut in the cargo lining must have a smooth
____ contour with no sharp corners. Sharp corners can cause a new crack or a tear.
S 348-016
(4) Use the abrasive paper to lightly rub the surface of the cargo lining.
NOTE: The surface of the cargo lining must be rubbed until it is
____ not glossy. The white Tedlar surface on some of the cargo linings must be removed until you see the glass fabric laminations.
S 118-017
(5) Clean the surface of the cargo lining with a cheesecloth or wiper that is moist with the solvent.
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F. Prepare the patch or doubler.
S 348-018
(1) Cut the patch, or a doubler and a plug patch of the same material (Class, Grade, and Type) as the cargo lining.
NOTE: The patch or doubler must extend around the damaged area by
____ no less than 3 inches. The plug patch must make a butt-joint along the edges of the cargo lining. The clearance between the plug patch and the cargo lining must not be more than
0.03 inch.
S 348-019
(2) Use the abrasive paper to lightly rub the surface of the patch or doubler.
NOTE: The surface of the patch or doubler must be rubbed until it
____ is not glossy. All the sharp corners and edges of the patch or doubler must be smooth. The white Tedlar surface must not be removed from the top side of the patch.
S 118-020
(3) Clean the surface of the patch or doubler with a cheesecloth or wiper that is moist with the solvent.
G. Prepare the adhesives (BMS 5-126 Type II and Type III).
NOTE: A clean metal container and a spatula can be used to mix the
____ adhesives. Use the hand cleaner (Epocleanse) immediately if the adhesives get on your skin. The pot life for the adhesives is 2 hours between the temperatures of 65°F and 80°F. Only mix the minimum quantity of the adhesives which is necessary to do the repair.
S 348-021
(1) Make the component A formula for the Type II adhesive:
(a) Mix 80 parts (by weight) of the Epon 828 or the DER 331 with 20 parts (by weight) of the Heloxy 68.
S 348-022
(2) Make the component A formula for the Type III adhesive:
(a) Mix 80 parts (by weight) of the Epon 828 or the DER 331 with 20 parts (by weight) of the Heloxy 68
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(b) Mix 6 parts (by weight) of the Cab-o-Sil with 100 parts (by weight) of the mixture in step (a).
S 348-023
(3) Make the component B formula for the Type II adhesive and the Type III adhesive:
(a) Mix 50 parts (by weight) of the Versamid 115 with 50 parts (by weight) of the Versamid 125 for each of the adhesives.
S 348-024
(4) Make the Type II adhesive:
(a) Mix 50 parts (by weight) of the component A formula (step (1)) with 50 parts (by weight) of the component B formula (step (3)).
S 348-025
(5) Make the Type III adhesive:
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