TASK 70-43-27-380-001
1 . General.
A.Epoxy polyamide is an erosion resistant, protective coating (Color Code 27038 - Black) for use in areas subject to corrosion. To apply this coating to aluminum and ferrous alloys refer to TASK 70-43-22-380-014, Paint - Epoxy Polyamide Coating for Aluminum and Ferrous Alloys.
2 . Materials.
Subtask 70-43-27-380-051
 
Product Identification
Consumable Code
 
Epoxy Polyamide Coating
C03-010  
 
Reducer
C04-029  
 
Abrasive Paper, 120-180 Grit, SiC, Wet/Dry
C10-141  
 
Cleaning Cloths
C10-182  
3 . Procedure.
Subtask 70-43-27-380-052
A.Prepare bare surface of composite material for painting as follows:
CAUTION:
DO NOT EXPOSE THE UNDERLYING FIBERS OR DAMAGE TO THE PART WILL OCCUR.
(1)Using 120-180 grit abrasive paper C10-141,   hand-sand the surface of the unfinished composite material. Sanding is to be performed dry.
(a)On new composites sand sufficiently to break the resin surface glaze.
(b)On existing composites that do not have surface glaze, lightly sand to remove surface contamination.
WARNING:
USE EYE PROTECTION WHEN YOU USE COMPRESSED AIR TO CLEAN, COOL, OR DRY PARTS OR TOOLS. PARTICLES CAN CAUSE AN INJURY TO YOUR EYES. DO NOT USE MORE THAN 30 PSIG (207 kPa). DO NOT POINT COMPRESSED AIR AT YOURSELF OR OTHER PERSONS.
(2)Clean the debris from the area to be repaired with clean, dry, oil-free compressed shop air.
(3)Mask areas around portion to be painted per Composite Masking Method 3 in TASK 70-46-01-350-030, Masking and Cleaning of Epoxy and Polyester Matrix Thermosetting Composite Materials.
WARNING:
CLEANING SOLVENTS ARE TOXIC AND HIGHLY FLAMMABLE. USE IN A WELL-VENTILATED AREA, AND TAKE PRECAUTIONS AGAINST FIRE.
(4)Clean surface to be painted. Refer to Composite Cleaning Method 4 or 5 in TASK 70-46-01-350-030, Masking and Cleaning of Epoxy and Polyester Matrix Thermosetting Composite Materials. Allow the part to dry completely.
(5)Mask clean surface to be painted per Composite Masking Method 4 in TASK 70-46-01-350-030, Masking and Cleaning of Epoxy and Polyester Matrix Thermosetting Composite Materials.
B.Apply epoxy polyamide coating C03-010   and reducer C04-029   as follows:
(1)Mix each individual component in its original container prior to use. Mix the coating and the reducer as specified by the manufacturer. Stir thoroughly and allow this mixture to stand at room temperature for 30 minutes minimum (chemical reaction time).
NOTE:
This waiting period will apply after the addition of reducer - if reducer is required.
NOTE:
For spray application, the two components may be thinned by the addition of reducer C04-029   as specified by the manufacturer.
(2)Remove masking from area to be painted. Refer to Step 3.A.(5).
(3)Spray the paint in repeated thin coats to produce a satisfactory surface finish of 0.003-0.005 inch (0.08-0.13 mm).
(4)Air dry painted parts for 30 minutes minimum.
(5)Do an inspection of the painted area for grit, seeds, runs, craters, and blisters. Use the inspection limits in the repair procedure, or the following:
(a)Grit, any number is acceptable. The total collected amount cannot be more than 0.062 x 0.062 x 0.010 inch (1.57 x 1.57 x 0.25 mm) high in any 1.0 square inch (645.2 sq mm) area.
(b)Seeds, any number is acceptable. The total collected amount cannot be more than 0.062 x 0.062 x 0.010 inch (1.57 x 1.57 x 0.25 mm) high in any 1.0 square inch (645.2 sq mm) area.
(c)Runs, cannot be more that 0.010 inch (0.25 mm) above the coating surface.
(d)Craters, any number is acceptable. The total collected amount cannot be more than 0.125 x 0.125 x 0.010 inch (3.18 x 3.18 x 0.25 mm) in depth in any 1.0 square inch (645.2 sq mm) area.
(e)Blisters, none permitted.
(6)Rework as required.
(a)Apply reducer C04-029   to cleaning cloth C10-182   and wipe surface to remove imperfections.
(b)Repeat Steps 3.B.(2) thru 3.B.(6).
WARNING:
MAKE SURE THE PAINT IS DRY BEFORE YOU PUT THE PARTS IN THE OVEN. WET PAINT CAN START A FIRE OR AN EXPLOSION.
(7)Oven cure at 175° ± 10°F (79° ± 6°C) for 60-90 minutes.
(8)Remove all masking and clean as required.