Repair Patch (Heat Cure Method) - Piper Cheyenne IIIA Airplane Maintenance Manual

PIPER AIRCRAFT
PA-42-720 (Advanced Trainer)
MAINTENANCE MANUAL
A. Storage (continued)
16. 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 comers of patch. Ensure dull side or gum contact face of repair patch is the
largest surface 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 0.50 inch 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
CELLOPHANE 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 completed without repositioning cell.
WARNING: CEMENTS AND SOLVENTS ARE FLAMMABLE. MIX AND APPLY CEMENT IN
WELL VENTILATED AREA.
WARNING: REPAIR CEMENT 5923C SHELF LIFE IS ONE YEAR FROM DATE ON
CONTAINER. DO NOT USE OUT DATED CEMENT.
NOTE: Mix and apply cement at minimum temperature of 70°F. Pot life of mixed cement is 20
minutes to one hour.
(i) Mix repair cement 5923C as follows:
(1.) Shake contents of part 2.
(2.) Pour contents of part 2 into part 1. Stir thoroughly, making sure entire contents of both
containers are are blended completely.
EFFECTIVITY:
28-10-00Jan
10/90