Procedures and Precautions
The stripping procedures described below are
general in nature. When stripping any aircraft surface,
you should consult the applicable MIM for the specific
procedures to be used. Stripping should be
accomplished outside whenever possible. If you must
strip aircraft surfaces in a hangar or other enclosure,
you should make sure you have adequate ventilation.
You should adhere to the following general procedures
and precautions during stripping operations:
Before cleaning and stripping, make sure
that the aircraft is properly grounded. This
will dissipate any static electricity produced
by the cleaning and stripping operations.
Where the paint remover may contact adhesives,
mask all seals, joints, skin laps, and bonded joints by
using the approved tapes and papers.
Apply the stripper liberally. Completely cover
the surface with a thick layer of stripper with a paint or
acid brush. The stripper should not be spread in a thin
coat like paint because it will not loosen paint
sufficiently for removal, and the remover may dry on
the surface of the metal. This would require it to be
Allow the stripper to remain on the surface long
enough for it to wrinkle and lift the paint. This may be
from 10 to 40 minutes, depending upon temperature,
humidity, and the condition of the paint coat being
removed. Reapply paint remover as necessary in the
areas where paint remains tight or where the material
Remove loosened paint and residual paint
remover by washing and scrubbing the surface with
fresh water, fiber scrapers, bristle brushes, and rags. If
water spray is available, you should use a
low-to-medium pressure stream of water. Apply it
directly to the surface while scrubbing the surface.
After a thorough cleaning, you should remove
masking materials and clean any residual paint from the
Rinse with water and clean the area with aircraft
cleaning compound (1 part MIL-C-85570 to 9 parts
water) to remove paint remover residue.
Paint can be mechanically removed with a flap
brush. The brush consists of many nonwoven,
nonmetallic, nylon flaps bonded to a fiber core. The
brush assembly (fig. 4-31) is made up of a flap brush,
flanges, and mandrel. Use a NO LOAD 3200 rpm
pneumatic drill motor to power the brush. Do not use
a flap brush that is worn down to within 2 inches from
the center of the hub. Continued use beyond this limit
may cause gouging due to loss of flexibility of the
fiber. When you use a flap brush, apply minimum
pressure to remove the most paint and the least metal.
Excessive pressure will cause some paints to melt,
gum up, and streak around the area being worked. For
safe and efficient operation, the direction of rotation
is indicated by an arrow imprinted on the inside of the
core. Wear eye protection when operating a flap brush,
and consult your maintenance instruction manuals for
limitations on corrosion removal.
Q77. What is the primary purpose of any paint finish?
Q78. When using paint removers, you should wear
what type of protective clothing?
Q79. What safety precaution must be taken before
cleaning and stripping old finishes on aircraft?
Q80. What type of motor should you use to power a
Figure 4-31.Flap brush and mandrel.