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Epoxy Information
By:Ian Johnston
Date: 10/10/1999, 2:34 am

Here is the information on epoxying cedar strip kayaks and canoes that I said I would post. This is pretty generic information and should be applicable to all brands of epoxy. Also this info is meant to give the first time builder an understanding of the process, not to change the process of experienced boat builders. Hope this will help, Ian Johnston

CUSTOMER SERVICES BULLETIN

CEDAR STRIP CANOES & KAYAKS

The materials and application techniques used in fiberglassing a cedar strip boat are similar to that of glassing any boat, but there are notable exceptions. Cedar strip boat shells are relatively flexible as they are covered with materials that will bend enough to resist fracturing, yet contribute to the rigidity of the craft. Canoes and kayaks are also kept as light as possible for both performance and transport considerations. For these reasons only light weight materials which will impart high strength are used in their construction.

The glass fabric best suited for cedar strip crafts is a woven fiberglass cloth. Fiberglass cloth has a higher strength/weight ratio than other glass fabrics, and are easier to apply. A 6 to 10 ounce cloth is generally used depending on the size of the boat. Usually three times the length of the boat by the girth is required in cloth. This provides enough to cover the entire boat inside and out, plus material for two "football" pieces for the bottom, inside and out.

All cedar, yellow and redwood, tend to be very oily and often create problems in the adhesion of fiberglass to cedar, therefore Aqua-Set Epoxy is recommended to laminate the cloth to the wood. Aqua-Set Epoxy'is noted for it's tenacious bonding characteristics to wet, oily and/or acidic woods as well as it's exceptional abrasion resistance. Aqua-Set Epoxy can be applied by brush, roller or squeegee. One litre of Aqua-Set Epoxy will saturate approximately 30 square feet of 6 ounce fiberglass cloth.

NOTE: Work safe. Be sure your work area is well organized and have all required tools, solvents and mixing containers on hand before starting this, or any project. Always wear protective clothing, gloves and goggles, and wear respiratory protection and work in well ventilated conditions.

PROCEDURES

1. Upon completion of finish sending the boat, cut a piece of cloth to fit the outside of the boat and trim excess material. Split a second hull length in two (lengthwise) and cut into two "football" shaped pieces for the bottom, inside and out.

2. Lay out one "football" piece over the bottom of the boat and smooth over the keel area. Mix approximately 450 mi of Aqua-Set Epoxy· Starting at one end of the boat, use a brush to saturate the Aqua-Set Epoxy through the cloth. Squeegee out the Aqua-Set Epoxy until the cloth is completely transparent and no air pockets are apparent. It is important not to have excess resin build-up as this will add unnecessary weight. Only enough Aqua-Set Epoxy is required to saturate the glass, and no more. Blending more Aqua-Set Epoxy as required, lay the large piece of cloth over the boat and saturate using the previous techniques mentioned. It is best to laminate this piece of cloth before the first layer has cured. If not, scuff-sand between layers for maximum adhesion.

3. After a thorough cure, scuff sand the fiberglass to remove any lumps or burrs. Apply a final coat of Aqua-Set Epoxy to fill small pores or pinholes and to smooth out the surface.

4. Repeat the above procedures for the interior of the craft. Once the lamination process has been accomplished, the finish must be protected against ultra-violet degradation· This can be accomplished by applying two coats of Gloucester Premium Spar Varnish or Endura Polyurethane #100 Clear. These coatings will prevent the wood from discolouring and provide a permanent hi-gloss finish.

GOOD LUCK!

Sample Bill of Materials:

Boat Specifications: Length - 16', Beam - 34", Depth - 14", Girth 52"

Materials Required: 16 yards 6 oz x 60" Fiberglass Cloth; 6 litre Aqua-Set Epoxy kit; 1.5 litre Aqua-Set Epoxy kit; 1 litre Xylene; 2 - 500 mi Polyurethane Clear Coating·

Messages In This Thread

Epoxy Information
Ian Johnston -- 10/10/1999, 2:34 am
Re: Urethane Adhesive Information
Ian Johnston -- 10/10/1999, 4:35 am
Re: Aqua-set Epoxy Information
Ian Johnston -- 10/10/1999, 4:49 am