Piper COMANCHE PA-24-180 Service Manual page 118

PIPER COMANCHE SERVICE MANUAL
k.
Msk are around hole wth tape and paper co protect surface. Cut piece of fiberglus mnu abouc
one inch larger thn the hole and one or more pieces of fiberglss cloth two inches larger hun the hole.
Brush catalyzed resin over hole, lay mat over hole and wet out with caalyzed resin. Use a daubing acon
with brush. Then apply addirional layer or layers of fibergla cloth to build up patch to the surface of
saucture Wet out each layer thoroughly with resin.
L
With a squeegee or broad knife, work out all air bubbles in the patch. Work from center co edge.
pressing patch firmly against the stuccure. Allow patch to cure for 1S to 20 minutes.
m. As soon as the patch begins co set up, but while sill rubbery, take a sharp knife and cut away
extr cloth and ma. Cut on outside edge of feathering. Sip
cut edges of structure. Do this before cure is
complete, to save extr sanding. Allow patch to cure oveniht.
n.
Using dry 80 grit sandpaper on a power under or sanding block. smooth patch and blend with
surrounding surface. Should air pockes appear while sanding, puncture and fill with catalyzed resin. A
hypodenic needle may be used to fill caities. Let cure and reand.
o.
Mix catalyzed resin and work into.patch with fuigen. Smooth carefully and work into any
crevces.
p. Cover with cellophane and squeegee smooth. Allow co cure completely before removing
cellophane. Let cure and resand.
q.
Brush or spray a coat of caulyzed resin to seal patch. Sand patch, finish by priming, again sanding
and applying color coat.
NOTE
Brush and hands may be cleaned in solvents such as aceone or
methylethylketone. If solvents are not available, a strong solution of
detergent and water may be used.
4-47. Srucual
Repans. Strucmtral repair methods used must be made in accordance with the regulanons
sec forth in FAA Advisory Circular 43-13-1. To assist in making repairs and/or replacements. Figures 4-8
thru 4-13 identifies the type and thickness of various skin material used. Never make a skin replacement or
patch plate from material other than the type of the original skin, or of a different thicknes thhan the
original skin. The repair must be as srong as the original skin. However, flexibility must be retained so the
surrounding areas will not receive extra ses.
It may be necessary to cut access holes to make skin repain in some ares of the airplane. Refer to
Figure 4-14 for typical access holes.
WARNING
NO access holes are permitted in any control surfaces.
WARNING
The use of patch plates for repair of all movable cal surfaces is
prohibited. The use of any filler material normally used for repair of
minor dens and/or materials used for filling the inside of surfaces is also
prohibited on all movable tail surfaces.
STRUCTURE
ISSUED: 8/1/72
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