Repair Patch (Heat Cure Method) - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
d. Apply both outside and inside patches for blisters between inner liner and fabric larger than 0.25
inch in diameter.e. Apply both outside and inside patches to repair holes and punctures. Apply both out-
side and inside patches to repair separations between outer plies larger than 1.0 inches in diameter.
NOTE
Slits or tears are limited to 6.0 inches maximum in length.
f. Apply outside patch only to external abraded or scuffed areas without fabric damage.
g. Trim loose laps as necessary provided a 5.0 inch effective band remains.
CAUTION
For each 10
°
drop in temperature from 70°F, add 20 hours cure
time. Do not air cure repairs below 60°F.
h. Clamp repair patches when performing air cure repair. Cure at room temperature of 70°F undis-
turbed for 72 hours.
i. Limit fitting repairs to loose flange edges, seal surface rework, and coat stock.
j. Do not exceed four heat cure repairs in the same area.
NOTE
Any damage not covered by the above the cell should be
returned for repair to: Loral Engineered Fabrics, 669 Goodyear
Street, Rockmart, Georgia 30153 - 0548.9-1 3b.
9-60. REPAIR PATCH (HEAT CURE METHOD)
CAUTION
Do not apply an outside and inside patch simultaneously. Apply
outside patch first.
a. Cut a patch from FT - 227 repair fabric to the size required to ensure a proper lap over the injury in
all directions.
1. Hold shears at an angle to produce a beveled edge (feather) on the patch.
2. Round corners of patch. Ensure dull side or gum contact face of repair patch is the largest sur-
face after beveling.
b. Wash one square foot of cell wall beyond damaged area in all directions.
c. Wash contact side of patch using a clean cloth dampened with Methylethylketone solvent.
d. Center repair patch over damaged area. Mark cell .50 beyond patch in all directions
CAUTION
Buff cell surface with care to avoid further damage.
e. Buff cell surface surrounding damaged area as marked and contact side of patch with fine emery
cloth to remove gloss.
f. Wash cell and patch surfaces two more times using a cloth dampened with MEK.
CAUTION
To prevent cement from sticking cell walls together, ensure cel-
lophane placed inside cell remains in place.
g. Tape a piece of cellophane inside the cell over the injury.
h. Fold cell so repair can be co mpleted without repositioning cell.
Revised: 3/31/94
FUEL SYSTEM
2L7