S 377-012
(3)
Refer to the manufacturer's instruction to mix the conductive coatings.
S 937-011
(4)
Identify the container with a label. Write the date and hour when the compound was mixed and the hour when the pot life ends.
NOTE: The conductive coating compound has a pot life of 4 |0.5
____ hours at 75 |0.5°F. Do not use the compound if its pot life has ended.
S 377-013
(5)
Let the conductive coating compound stay for not less than 30 minutes before it is used.
S 957-014
(6)
Apply masking tape to all adjacent areas.
S 377-015
WARNING: DO NOT APPLY PAINT THAT HAS METAL PARTICLES ON THE ANTENNA
_______ FAIRINGS. THE METAL PARTICLES IN THE PAINT CAN CAUSE THE ANTENNA TO OPERATE INCORRECTLY.
(7)
Apply the conductive coating compound with a spray gun or use a brush. Make sure the dry film thickness is 0.6 |0.2 mil (0.006 |0.002 inch).
S 377-016
(8)
Let the conductive coating cure before you measure the conductivity (Fig. 702).
NOTE: Let the conductive coating that is in fastener holes cure for
____ not less than 20 minutes before you install the fasteners.
S 767-017
(9) Do these steps to measure the conductivity of the conductive coating by the Ohms Per Square Method (Fig. 703):
(a) Push the two probes of the multimeter against the conductive coating.
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180
170 160 150 140 130 120 110 100
90
80
70
TEMPERATURE (`F)
15 30 45 60 75 90 105120
TIME (MINUTES)
Drying Time - BMS 10-21, Type III
Figure 702
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(b)
Measure the resistivity between the two strips by use of the multimeter.
(c)
The measured value multiplied by 10 will give the value of resistivity in ohms/square.
(d)
The maximum permitted resistivity is 300,000 ohms/square.
S 107-018
(10) Do these steps, if the resistivity of the conductive coating is more than 300,000 ohms/square:
(a)
Sand the area with 240 grit or finer abrasive paper. Do not sand through the coating.
(b)
Remove the remaining particles with a clean cheesecloth that is moist with aliphatic naphtha. Then dry the surface with a clean cheesecloth.
(c)
Apply the new layers of conductive coating. Refer to the above procedure.
(d)
Do the above steps to measure the conductivity of the new layers of coating.
S 377-019
(11) Do these steps, if you are to apply a topcoat.
(a) Rub the conductive coating with a clean cheesecloth that is moist with solvent.
ALUMINUM FOIL STRIPS
Method for Measuring Resistance of Conductive Finish by the Ohms Per Square Method
Figure 703
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(b) Rub the surface with a clean, dry cheesecloth before the solvent dries. Clean the surface until no soil or dust
(c) particles are found on a clean cheesecloth.Apply BMS 10-79 Type II or III in a uniform coat, free of runs and wrinkles, to a dry film thickness of 0.5 to 0.8 mil within 24 hours after application of conductive coating (AMM 51-24-11/701).
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