(4)
Apply Dow 1. solution for 1 minute and wipe dry with clean cloth. (Mix Dow 1. solution in accordance with manufacturer’s specification.)
(5)
Apply Dow 19. solution for 1 minute and wipe dry with clean cloth. (Mix Dow 19. solution in accordance with manufacturer’s specification.)
(6)
Hot air-dry surface for 5-10 minutes using a heat gun. Do not allow surface temperature to exceed 250°F.
CAUTION: POT LIFE OF MIXED MATERIALS IS 8 HOURS. ADHERE STRICTLY TO POT LIFE LIMIT OF MIX; MARK TIME AND DATE ON CUP. ABSOLUTELY DO NOT REFRIGERATE OR ADD SOLVENT TO EXTEND TIME.
(7)
Touch up with an airbrush or soft brush; do not use cotton swabs. Airbrushing is the preferred method. Allow 45 minutes reaction time after mixing base resin and catalyst thinner together before applying. Apply primer and topcoat in accordance with drawing requirements.
NOTE: For paint mixing and curing, refer to applicable paint specification. Mix materials at room temperature (77° ± 10°F).
(8)
Air-dry newly applied paint for 60 minutes before using heat gun.
(9)
Apply heat to newly painted surface with a heat gun. Allow 10-12 inches distance from end of heat gun to painted surface. Do not exceed 200°F on part. Heat part 30-45 minutes to cure. Paint must be fully cured prior to packaging part.
4. Repairing Aluminum Parts
A. Method No. 404A: Minor Surface Defect Repair
Repair minor surface defects on aluminum-alloy parts as follows:
NOTE: Remove minor surface defects only if the defect is detrimental to operation and removal will not cause or increase leakage or compromise sealing functions.
(1)
Smooth out minor surface burrs, scratches, or galling, using abrasive cloth (Federal Specification P-C-451) (SECTION VII).
(2)
Treat areas where base metal is exposed, as follows:
WARNING: SOLVENT VAPORS ARE TOXIC AND FLAMMABLE. DO NOT INHALE VAPORS. OBSERVE ALL FIRE PRECAUTIONS.
(a) Clean surface with solvent (Federal Specification P-D-680, Type I) (SECTION VII).
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WARNING: USE CORRECT PERSONAL PROTECTION. ALKALINE CLEANING SOLUTIONS ARE HAZARDOUS. AVOID INHALING FUMES OR MIST. AVOID CONTACT WITH SKIN. AFTER USE, WASH HANDS AND FACE THOROUGHLY.
(b)
Immerse part in alkaline cleaner solution (Method No. 402A) for 10 to 15 minutes.
(c)
Scrub surface with a stiff fiber bristled brush, until surface is clean.
(d)
Rinse in warm tap water at 80 to 110F (27 to 43C).
WARNING: USE CORRECT PERSONAL PROTECTION. COMPRESSED AIR WILL CAUSE LOOSE PARTICLES THAT CAN GET IN YOUR EYES. COMPRESSED AIRFLOW CAN CAUSE CUTS, DO NOT POINT IT AT YOUR SKIN.
(e)
Pressure air-dry using clean, dry, filtered compressed air at 20 psig (137,89 kPa) maximum.
(f)
Spot treat areas where base metal is exposed, with aluminum touch-up solution (Method No. 402E).
(g)
Allow treated area to remain wet for one minute.
(h)
Rinse in warm tap water at 80 to 110F (27 to 43C).
WARNING: USE CORRECT PERSONAL PROTECTION. COMPRESSED AIR WILL CAUSE LOOSE PARTICLES THAT CAN GET IN YOUR EYES. COMPRESSED AIRFLOW CAN CAUSE CUTS, DO NOT POINT IT AT YOUR SKIN.
(i)
Air-dry using clean, dry, filtered compressed air at 20 psig (137,89 kPa) maximum or oven dry for 30 minutes at 175 to 225F (79 to 107C).
B. Method No. 404B: Heavy Corrosion, Hard Carbon, Paint, and Scale Removal Remove heavy corrosion, hard carbon, paint, and scale from aluminum-alloy parts as follows:
(1)
Mask any surface that might be damaged by abrasive blasting.
(2)
Place part in a standard sandblast cabinet.
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