Frequently Asked Questions
What is Kay-Cel® Core?
Kay-Cel Core is a high-density polyurethane foam panel reinforced with fiberglass to increase core
mechanical properties. It is a closed-cel foam that will not absorb water…will not rot. Kay-Cel core material
is 30-50% lighter than marine grade plywood.
What are the uses for Kay-Cel Core?
Kay-Cel Core is primarily used as a wood replacement in many applications including marine applications. Typical
marine applications would be the transom, stringers, bulkheads, local reinforcement and deck.
How do I cut Kay-Cel Core?
Normal woodworking tools are adequate for cutting the material. Best to use a carbide cutting surface when
cutting a large volume as the fiberglass in the sheet is abrasive to tooling. Wear proper safety gear such
as dust mask, safety glasses and gloves.
How do I laminate Kay-Cel Core?
The material must be dry and free of dust. Best practice is to pre-coat surface of the board with resin before
applying fiberglass layers for proper adhesion. Spreading resin on board is best done using a roller. Must fill
in tiny bubbles in decking material to avoid blisters caused by heat. Make sure and remove any release agents
or shiny spots on the material for best adhesion. A proper mix ratio of catalyst and resin is required to resin
manufacturers specifications. Do not allow straight catalyst or unmixed catalyst to become trapped during
What kind of resin can be used for fiberglass lamination?
Most resins are compatible with Kay-Cel Core including polyester, vinyl ester and epoxy resins.
What adhesives can I use for bonding multiple pieces together?
Many different adhesives are used in bonding the material together. Epoxy, polyurethane, 5200, methacrylate
are a few examples. Proper testing of adhesive and Kay-Cel Core material is recommended based on your application.
What thickness of Kay-Cel and fiberglass should I use in replacing rotted wood of my boat?
Try to mirror what the original engineers did to manufacture the boat. If they used ¾” plywood then use ¾”
Kay-Cel Core. If they glassed the rotten plywood on both sides then do the same. The good thing is that
it will be the last time you replace the rotted subsurface of your boat.
How do I store Kay-Cel Core?
Store the material indoors out of direct sunlight. Direct sunlight will cause the material to turn colors
and fade. Long-term exposure to sunlight will cause the material to degrade. The core material is made to
be encapsulated in fiberglass or coated for UV protection. Keep boards free from moisture, dust and debris.
Clean shop accordingly. The material must be dry when processing. Moisture must not be on the surface when
laminating or applying a coating.
What safety equipment must be used?
The use of a dust mask, safety glasses, and gloves is highly recommended.
What if see color variation in the sheets of Kay-Cell core?
Color variation is normal. Kay-Cel Core can vary from a light grey to a darker grey. Color does not affect
mechanical strength nor bonding characteristics of the boards.
Purpose Scope: These guidelines are for the general use of Kay-Cel Core material and don’t
replace generally accepted good shop practices, common sense, and testing of material for suitable application.