Piper Cherokee Six - Page 136

PIPER
CHEROKEE
SIX
SERVICE
MANUAL
d. Work the
mixture
of resin, fibers
and catalyst
intothe
damaged
area, using
the sharp point
of a putty knife
or stick to press
it into the bottom
of the hole and
to
puncture any
air bubbles
which may
be present.
Fill the
scratch or
hole above
the surrounding
undamaged
area
about 1/16
inch.
e. Lay a piece
of cellophane
orwaxed paper
over the repair
to cut off air and
start the
cure
of gel
mixture.
f.
Allow the gel
to cure 10 to 15
minutes until it
feels rubbery to
the touch.
Remove the cellophane
and trim
flush with the surface,
using a sharp
razor blade
or knife.
Replace the cellophane and allow
to cure completely for 30 minutes
to
an hour.
The patch will shrink
slightly below
the structure
surface as it cures.
(If wax
paper is used,
ascertain
wax is removed
from surface.)
g.
Rough up the bottom
and edges
of the hole with the
electric burr
attachment
or rough sand paper.
Feather hole
into surrounding
gel coat, do
not undercut.
h.
Pour out a small
amount of resin,
add catalyst
and mix thoroughly,
using
a cutting motion
rather
than stirring.
Use
no fibers.
i. Using the tip of a putty
knife or finger tips, fill the
hole to about 1/16 inch
above the surrounding
surface with
the gel coat mixture.
j .
Lay a piece of
cellophane over
the patch to start
the curing process.
Re-
peat
step f, trimming patch
when partially cured.
k. After trimming the patch,
immediately place another small
amount of gel
coat on one edge of the patch
and cover with cellophane.
Then, using a squeegee
or the
back of a razorblade, squeegee
level with area surroundingthe patch,
leave
the cellophane on patch for one
or two hours or overnight, for
complete cure.
1. After repair has cured
for 24 hours, sand patched
area, using a sanding
block with fine wet
sandpaper. Finish by priming,
again sanding and applying
color coat.
4-22. FIBERGLASS FRACTURE AND PATCH REPAIRS.
a. Remove
wax, oil and
dirt from around
the damaged
area with acetone,
methylethylketone
or equivalent.
b.
Using a key hole
saw, electric
saber saw, or sharp
knife cut away
ragged
edges. Cut back
to sound material.
c.
Remove paint
three inches
back from
around damaged
area.
d. Working inside the structure,
bevel the edges to approximately
a 30 degree
angle and rough-sand the
hole and the area around it, using
80-grit dry paper.
Feather back for about two inches
all around the hole. This roughens
the surface
for
strong bond
with patch.
e. Cover a piece of cardboard
or metal with cellophane. Tape
it to the out-
side of the structure, covering the hole completely. The cellophane should face
toward the inside of the structure. If the repair is on a sharp contour or shaped
area, a sheet of aluminum
formed to a similar contour
may be placed over the
STRUCTURE
Issued:
8/17/72
1F16