Technical data

Only those aluminum wools and brushes speci-
fied shall be used to agitate metallic surfaces
during finish system removal operations. Other
types of metallic wools and brushes, such as
steel, copper, brass, beryllium copper, etc., shall
not be used as they will either embed in or smear
on the metallic surface and cause severe galvanic
corrosion problems.
NOTE
If a polysulfide primer/polyurethane topcoat fin-
ish system is being removed and the first appli-
cation of chemical remover takes off the topcoat
but not the primer, the second and subsequent
applications shall be with one of the chemical
removers specified in this manual for removing
polysulfide primer.
k. Repeat the removal sequence, Paragraph 2.7, step g
through Paragraph 2.7, step j, in the area being worked
as necessary to remove the finish system down to bare
metal up to a maximum of three times. For the second
and all subsequent applications of chemical remover
agitate the surface with A-A-58054, Type I, Grade C
nylon abrasive mat; A-A-1044, Type II, Class 1, Form
A, aluminum wool; and/or A-A-3118, Type I, Class A7
aluminum wire brushes to assist in the removal opera-
tion.
NOTE
• A-A-58054, Type I, nylon abrasive mat is
avai1ab1e under NSN 5350-00-967-5092 for
10 sheets of Grade C (medium) material.
• A-A-1044, Type II, Class 1, Form A, (PN
AA1044-B-1-A), aluminum wool is available
under NSN 5350-00-286-4851 for a one
pound roll or 5350-00-312-6129 for 25 one
pound rolls.
• A-A-3118, Type I, Class 7, (PN A-A-3118/A7)
aluminum wire brushes are available under
NSN 7920-01-067-6192 for one brush.
l. As soon as the finish system has been removed down to
bare metal or the final attempt at overall chemical
removal has been completed and the chemical remover
and finish system residue has been scraped from the
surface with a rubber bladed squeegee in the area being
worked, flush the area thoroughly with hot water at a
temperature of 100° F to 120° F and a pressure of
150-250 PSI. Start at the lowest point and work upward
using care to keep the water off adjacent areas from
which the finish system will be removed.
NOTE
• If hot water is not available, fresh tap water at
hydrant pressure may be used for the flush
operation. However, it should be well under-
stood that this will make the final cleaning/
washing step much more difficult and require
additional man-hours and flow time to accom-
plish, because cold water tends to gel waxy
compounds used in chemical removers and
redeposit them on the surface.
• With prior written aircraft Systems Program
Director (SPD) approval, Medium Pressure
Water (MPW) methods in Paragraph 2.12
(water only-no baking soda) may be used
instead of Paragraph 2.7 step i through step l
to enhance paint removal with environmen-
tally compliant removers in Paragraph 2.6.4
after their required dwell time is reached.
• When removing alkyd base primer having no
topcoat, flush the area with water as soon as
possible after it has been loosened by the
chemical remover and scraped from the sur-
face as it tends to readily redeposit on the
surface if the surface becomes dry thus requir-
ing another application of chemical remover.
m. After the area being worked has been thoroughly flushed
with water, remove tape used for masking within the
area by hand; or, as an alternate, remove it with the hot
water at the same time the area is being flushed.
n. Remove any residual finish system from very stubborn
spots and areas covered with tape during the general
removal operation using care to prevent chemical re-
moval materials from entering into and becoming en-
trapped in confined areas and/or causing damage to
structure, components or materials. Apply either the
same chemical removers used for the general removal
operation, or specification MIL-T-81772, Type I or II
thinner, and/or specification TT-E-751 ethyl acetate by
dabbing them on the spots with a small non-metallic
bristle brush. Agitate the spots with the same materials
listed for agitation during the general removal operation
and/or nonmetallic/plastic scrapers while the chemical
remover or solvent is on the surface. Wipe the loosened
finish system and chemical remover off the surface with
a cotton rag; and if necessary, abrade the remaining
finish system off the surface in accordance with the
mechanical removal procedures in Paragraph 2.9 with
materials in Table 2-1, Table 2-2, and Table 2-3. Wipe
the area from which the finish system was removed with
a cotton rag wetted with fresh water, and then dry with
a clean cotton rag.
o. If the area just completed is the final area from which
the finish system is to be removed, proceed directly to
TO 1-1-8
2-10