2.
Pour out a small amount of resin, add catalyst, and mix thoroughly (use a cutting motion rather than stirring). Use no fibers.
3.
Using tip of a putty knife or fingertips, fill hole to about one-sixteenth of an inch above surrounding surface with gel coat mixture.
4.
Lay cellophane over patch to start curing process. Repeat step f, trimming patch when partially cured.
5 . After trimming patch, immediately place small amount of gel coat on cut edge of patch and cover with cellophane. Use a squeegee or the back of a razor blade, squeegee level with area surrounding patch. Leave cellophane on patch for 1 or 2 hours or overnight for complete cure.
6. After repair has cured 24 hours, sand patched area using a sanding block with fine wet sandpaper. Finish by priming, sand again, and apply color coat.
FIBERGLASS FRACTURE AND PATCH REPAIRS
1.
Remove wax, oil, and dirt from damaged area with acetone, methylethylketone, or equivalent.
2.
Use a key hole saw, electric saber saw, or sharp knife to cut away ragged areas. Cut back to sound material.
3.
Remove paint three inches back from damaged area.
4.
Use 80-grit dry paper and working inside the structure, bevel edges to approximately a 30 degree angle and rough-sand hole and area around it. Feather back for about two inches all around hole to roughen surface for strong bond with patch.
5.
Cover a piece of cardboard or metal with cellophane. Tape it to outside of structure. Completely cover hole. Cellophane must face toward inside of structure. Repair to a sharp contour or shaped area requires a sheet of aluminum formed to a similar contour to be placed over area. The aluminum must be covered with cellophane.
6.
Prepare a patch of fiberglass mat and cloth to cover area two inches larger than hole.
7.
Mix small amount of resin and catalyst, (enough for one step) per kit instructions.
51-10-00 Page 51-8 Issued: April 1, 1997
3B20
8.
Thoroughly wet mat and cloth with catalyzed resin. Daub resin to mat, then to cloth. Mat must be placed on structure surface with cloth on top. Use enough fiberglass cloth and mat reinforcements to maintain the original surface strength. Use extra layers of cloth if the damage was a stress crack.
9.
Lay patch over hole (inside of structure). Cover with cellophane, and squeegee from center to edges to remove all air bubbles. Air bubbles will show white and must all be worked out to edge. Remove excess resin before it gels. Allow patch to cure completely.
10.
Remove cardboard or aluminum sheet from outside of hole and rough-sand patch and hole edge. Feather edge of hole about two inches into undamaged area.
11.
Mask area around hole with tape and paper to protect surface. Cut a piece of fiberglass mat about one inch larger than hole. Cut one or more pieces of fiberglass cloth two inches larger than hole. Brush catalyzed resin over hole. Lay mat over hole and wet out with catalyzed resin. Brush with a daubing action. Then apply additional layer or layers of fiberglass cloth to build up patch to surface of structure. Wet out each layer thoroughly with resin.
12.
Work out all air bubbles in patch using a squeegee or broad knife. Work from center to edge pressing patch firmly against structure. Allow patch to cure 15 to 20 minutes.
13.
As soon as the patch begins to set up, but while it is still rubbery, use a sharp knife and cut away extra cloth and mat. Cut on outside edge of feathering. Strip cut edges of structure before cure is complete to save extra sanding. Allow patch to cure overnight.
14.
Use dry 80-grit sandpaper on a power sander or sanding block to smooth patch and blend with surrounding surface. Should air pockets appear while sanding, puncture and fill with catalyzed resin. A hypodermic needle may be used to fill cavities. Let cure and sand.
15.
Mix catalyzed resin and work into patch with fingers. Smooth carefully and work into crevices.
16.
Cover with cellophane and squeegee smooth. Cure completely before removing cellophane. Sand the area.
17.
Brush or spray catalyzed resin to seal patch. Sand and finish by priming. Sand again and apply color coat.
—Note —
Clean brush and hands in solvent such as acetone. Use a strong solution of detergent and water if solvents are not available.
ADDING LAYERS TO UNDAMAGED AREAS.
1.
Rough sand area to be laminated with 80 grit dry sandpaper.
2.
Thoroughly clean area to be laminated with acetone, MEK, or equivalent.
3.
Mix resin and catalysts according to the manufacturers instructions. Mix only enough to be used one step at a time.
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