Repairing Major Damage; Stress Lines; Painting The Repair; Safety Walk Repair - Surface Preparation - Piper PA-44-180 SEMINOLE Maintenance Manual

REPAIRING MAJOR DAMAGE: (Larger than 1 inch in diameter.) (Refer to Figure 51-8.)
A. Make a patch of same material and cut slightly larger than section being repaired.
B . When appearances are important, large holes, cracks, tears, etc., are repaired by cutting out
d a maged area and replacing with a piece of similar material.
C. When cutting away damaged area, under cut perimeter and maintain a smooth edge. The patch or
plug should also have a smooth edge to ensure a good fit.
D. Coat patch with solvent adhesive and firmly attach it over damaged area.
E. Let the patch dry for approximately 1 hour before any additional work is performed.
F. Fill hole, etc. with repair material. A slight over filling of repair material is suggested to allow
for sanding and finishing after repair has cured. If patching compound is used, repair should be
made in layers, not exceeding a 1/2 inch in thickness at a time. Allow compound to cure and
ensuring a good buildup of successive layers.
STRESS LINES: (Refer to Figure 51-9)
A. Stress lines produce a whitened appearance in a localized area. They are generally caused by
severe bending or impacting of material. (Refer to Figure 51-10.)
B. To restore material to original condition and color, use a hot air gun or similar heating device to
apply heat to affected area. Do not overheat material.

PAINTING THE REPAIR:

NOT ALL LACQUERS OR ENAMELS CAN BE USED ON
THERMOPLASTIC. SOME PAINT SOLVENTS WILL
AFFECT AND DEGRADE THE PLASTIC PROPERTIES.
DO NOT USE HARD, BRITTLE COATINGS IN FLEXING,
I M PA C T, OR HIGH STRESS AREAS. SUCH COAT I N G
M AY CRACK, CREATING A WEAK AREA.
A. An important factor in obtaining a quality paint finish is the proper preparation of the repair and
surrounding area before applying any paint.
B . Clean parts before painting with a commercial cleaner or a solution made from 1/4 cup of
d e t e rgent mixed with one gallon of water.
C. Use lacquer or enamel paint for thermoplastic repair.
Do not use hard, brittle coatings in flexing, impact, or high stress areas. Such coating may crack,
creating a weak area.
SAFETY WALK REPAIR
SURFACE PREPARATION
1. Clean all surfaces with a suitable cleaning solvent to remove dirt, grease, and oils. Apply solvents by
dipping, spraying, or mopping.
2. Check no moisture remains. Wipe surface with a clean dry cloth.
3. Outline the area to which liquid safety walk compound is to be applied, and mask adjacent surfaces.
For newly painted surfaces, allow 2.5 hours minimum drying
time before application of safety walk.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
—CAUTION—
—CAUTION—
—NOTE—
2L21
51-14-01
Page 51-13
Revised: June 20, 1995