(g) Apply a second coat of adhesive
(item 18, table 2-11) to buffed areas of patch and cell
innerliner and allow to dry until tacky. Adhesive can
become tacky within 2 to 4 minutes, depending on
ambient temperature and humidity. Perform knuckle
exceeded, reapplication of one
coat of adhesive may be done
only once (total of three coats). If
remove adhesive from applied
area using, acetone and/or buffing
(h) If necessary to restore tack of the
cemented surfaces, use a piece of cheesecloth (item 16,
table 2-11) dampened with acetone (item 3, table 2-11)
and lightly wipe over cemented areas. Allow solvent to
evaporate 10 to 20 seconds or until cemented areas
become "tacky." Wear gloves (item 4, table 2-11).
(i) While adhesive is still tacky, apply
patch to cemented area of the cell innerliner, centering
patch over hole. With a one-inch, or smaller roller (item
20, table 2-11), roll the patch to the cemented area and
roll it down a 1/2 inch to 1 inch across at a time so as
not to trap air between patch and innerliner.
(j) For a hole penetrating the entire cell
wall, follow steps (a) through (g) above for application of
an external patch, except use fabric (item 25, table 2-
11) patch material.
(k) Place a 10 to 25 pound force by
damping (C-damp (item 21, table 2-11) and two pieces
of wood (item 22, table 2-11)), shot bag (item 23, table
2-11), etc., if practical on repair. Polyethylene, waxed
paper (item 24, table 2-11) should be placed between
the patch and force applying device to prevent sticking
of the force applying device to the repair.
Allow repair to remain undisturbed
for at least 8 hours. The fuel cell should not be returned
to service for 24 hours after a cold patch has been
applied, which is the time required for the adhesive to
become fully cured, at a temperature between 60 °
workmanship, no loose edges, no voids and adhesive
fully cured. If there is a defect in repair, recement per
hangers/loops shall be performed as follows:
Acetone and repair adhesives are
flammable and toxic. Keep away
from heat, sparks and open flame.
Wear safety glasses, gloves and
protective clothing to prevent
contact. Wear a NIOSH approved
air-purifying respirator for organic
ventilated area. If contact occurs,
flush areas with water and get
medical attention. If ingestion
occurs get medical attention at
(a) Clean all bonding surfaces using a
piece of dean cheesecloth (item 16, table 2-11)
dampened with acetone (item 3, table 2-11). Wear
gloves (item 4, table 2-11).
(b) Lightly hand buff surfaces to be
bonded with emery cloth (120 grit) (item 17, table 2-11).
(c) Clean buffed areas using a piece of
dean cheesecloth (item 16, table 2-11) dampened with
acetone (item 3, table 2-11). Wear gloves (item 4, table
2-11). Allow cleaned areas to dry.
WARNING Repair adhesive is flammable and should be
kept away from any ignition source.
Adhesive materials should be kept
containers in a cool, dry place.
(d) Refer to paragraph c(1)(e) for
(e) Apply one coat of adhesive (item
18, table 2-11) to buffed surface of hanger and buffed
area of cell, allow to dry 20-60 minutes.
Change 2 2-64