FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 6. Corrosion, Inspection, and Protection | 9. Magnesium and Magnesium Alloys | 6-152. Example of Removing Corrosion From Magnesium
9/8/98
AC 43.13-1B
(b) Add chemicals to water in the or
der shown.
(c) Stir vigorously for at least
15 minutes, either mechanically or by air agi
tation, to ensure that the solution is saturated
with calcium sulfate. (Let solution stand for
15 minutes before decanting.)
(d) Prior to use, decant solution
(avoid transfer of undissolved calcium sulfate)
into suitable containers (polyethylene or glass).
(e) Apply solution by brush, swab, or
flow on using low-pressure spray (non
atomizing) until the metal surface becomes a
dull color (the color can vary from green-
brown, brassy, yellow-brown to dark-brown).
For good paint adhesion, a dark-brown color
free of powder is considered best. The color
may vary in using different vendors’ materials.
NOTE: Too long an exposure to the
brush-on solution produces coatings
that will powder and impair adhesion
of applied paint finish/films.
(f) Observe the coating closely dur
ing the treatment for color changes, rinsed with
cold running water when the desired condi
tion/color is reached and air dried. Preparation
and use of test panels made of the same mate
rial and under the same conditions, before
starting the actual treating operation may be
used as to determine the application time re
quired to produce the required coating. A
good coating is uniform in color/density, ad
heres well and is free of loose powder.
l. Apply primer and top coat finish
m. Remove masking and protective cov
erings.
6-153.6-163. [RESERVED.]
Par 6-152
Page 6-33 (and 6-34)