AIR TRACTOR AT-502A, Maintenance Section

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Maintenance Page 50 Air Tractor, Inc.
March 14, 2018 AT-502A/502B/504
STRIPPING AND RE-PAINTING PARTS
Stripping and Re-painting Aluminum Parts
1. The paint stripper most effective on urethane paint is Turco #5351.
2. The stripper is either sprayed on with a barrel pump or applied on small parts with a large paint brush. If
sprayed on be sure to consider wind direction so that over-spray will not damage surrounding vehicles or
aircraft.
3. When applying stripper, wear protective clothing and safety goggles.
4. Apply a medium to heavy coat of stripper. Temperature should be 50
o
F or warmer for best results.
Allow stripper to react with paint and remove with special brush having stiff bristles that will not soften
with stripper.
5. Spray on a second light coat of stripper as necessary and remove remaining paint with brush.
6. Rinse thoroughly with (approx. 150
o
F) water under pressure. Be sure entire film of stripper is removed.
7. Apply Acid Etch with Scotch Brite pads and scrub metal surfaces thoroughly. Rinse with cold water.
8. Before the part is dry, apply generous amounts of Alodine with a clean white rag. The Alodine should act
within two or three minutes and when rinsed off with cold water should leave a very light gold surface.
Do not leave the Alodine too long or allow it to dry as a dark brown film will result which is undesirable
and should be removed and the part reprocessed.
9. When the part is completely dry, apply a coat of High Solids Epoxy Primer:
9.1. Mixing ratio is 4 parts Pigmented Component and 1 part Adduct. Always follow
manufacturer recommended mixing ratios.
9.2. Surfaces must be clean and free of grease, dirt, oil, rust, fingerprints, and other
contaminants to insure optimum adhesion and performance properties. Parts may be cleaned using an
alcohol soaked soft rag.
9.3. Apply primer using conventional spray equipment or HVLP spray equipment.
9.4. Ideal coating thickness is 0.5 mils dry.
9.5. Spray coatings with smooth, even strokes. Runs and sags are to be avoided.
9.6. Application temperature should be between 65
o
-100
o
F.
9.7. Epoxy primer should be allowed to flash before recoating with epoxy primer.
9.8. Air dry time to topcoat at 77
o
-100
o
F is 2 hours minimum.