Commonly used chemical solvent used to wipe clean tools and equipment of polyester resin. Also known as Di-methylketone. Used for cleaning composite surfaces prior to bonding and also metal surfaces prior to other treatments. Classed as “Seriously Flammable” with a flashpoint of –4 F (-20 C). Has a high evaporation rate. Should not be used to remove uncured epoxy resin from tools and other items.

A wax solution used to help Epoxy Resin limit the Fish Eyes, blush, and orange peel. Does not need to be added to Epoxy for a Sanding Coat.

Air is a term used for little bubbles under the lamination, caused by either not enough resin or the cloth has been pulled too tightly.  Also see DRY SPOT.
Ratio of base to height or length to width. A high aspect ratio fin is long and narrow.

This term is used for the process when catalyzed lam resin is pushed back into the cloth where there was AIR, DRY SPOT, or some imperfection in the lamination process. Ideally this is done prior to the Hot Coat/Sanding Coat.

A lightweight wood from the balsa tree “Ochroma Lagopus”, used to make surfboards. Varies in density from (typically) 6-18 lbs per cubic foot. The word balsa itself is Spanish meaning raft, in reference to its excellent floatation qualities. In Ecuador, where much balsa is harvested, it is known as Boya, meaning buoy.

Belly is a term used to describe a rounded surfboard bottom, when viewed from the front or rear (not from the side).

Foam surfboard core prior to shaping. May be ordered in any number of shapes, thicknesses, densities, with preset or custom rockers. Common materials are PU (Poly Urethane) or EPS (expanded Poly Styrene).

CABOSIL (Aerosil)
Fumed Silica, used for altering the properties of resin to add viscosity or increase bond strength. Use in combination with other fillers to improve working properties and minimize draining with polyester and epoxy resins. Cabosil/Aerosil (2 brand names) can make sanding more difficult. See Milled Fiber (used to add strength), microballoons (easier sanding, light), Q-Cell

Computer-aided design/computer-aided manufacturing.

Polymer fibers produced by the pyrolysis (incineration that chemically decomposes organic materials by heat in the absence of oxygen) of organic precursor fibers such as rayon, the polymer polyacrylonitrile, and pitch in an inert atmosphere. The term is often used interchangeably with “graphite”; however, carbon fibers and graphite fibers differ in the temperature at which the fibers are made and heat-treated, and the amount of carbon produced.

A substance that changes the rate of a chemical reaction without itself undergoing permanent change in composition or becoming a part of the molecular structure of the product. A catalyst markedly speeds up the cure of a compound when added in minor quantity as compared to the amounts of primary reactants. (See also; MEKP)

Cant is the angle a fin makes relative to the bottom of the board. When a board is upside down with the fins pointing up, if the fins point straight up (90 degrees) they have no cant. Canted fins point slightly outward, so the tip of the fin is farther away from the stringer (toward the rail) than the base of the fin.

Channels are grooves or concave shapes in the bottom of a surfboard, running from front to back, although typically not for the whole length of the surfboard. The purpose of the channels is to propel more water through the board, converting the water flow into forward thrust.

1) Resin applied to wood before laminating as a pre-treatment, to prevent dry spots in the lamination caused by wood soaking up the resin.
2) Basting of laps or low spots with laminating resin before hot coating is sometimes called a cheater coat

A chine is a (typically) hard-edged angle sometimes used on the bottom of a rail, often at the nose of a long board. Chines can be deep or shallow, wide or narrow, blended or sharp. Boat hulls often have chines.

A fine weave of woven fiberglass.

A concave is an area on the bottom of a surfboard that not flat but curved from rail to rail, thus making the bottom of the board higher off the water in the center than at the rails. Concaves are often used under the nose of the board (single concave) or in pairs between side fins (double concave) and are intended to provide lift or facilitate water flow by altering rocker.

The polymerization or the transforming from the liquid to the solid state with maximum physical properties, including hardness.

When laminating a board, this is a method where you tape off where you want your lap line to end on the opposite side of the board from which you are laminating. When the resin begins to gel, you flip the board and cut along this tape-line to leave a smooth, clean lap-line. This is the ideal method when working with pigments/tints.

The deck is the top of the surfboard (where the feet and the wax go!) Decks can be flat, or domed. A surfboard with a domed deck is thickest in the center (along the stringer) and thinner along the rails, so that the top surface of the surfboard is curved if viewed from the front or rear of the board.

Separation of the layers of material in a laminate, either local or covering a wide area. Can occur in the cure or subsequent life. Physical separation or loss of bond between laminate plies. Severe heat will often be the cause of a delamination.

Damaged area on a surfboard; fractured glass, crushed foam, etc.

In laminated glass, an area over which the resin and the glass have not bonded and dry cloth weave is evident.

Fiberglass fabric, the standard in the industry for most surfboard construction. E Glass is a family of glasses with a borosilicate composition; also known as “Electrical glass” as it is suitable for electrical laminates because of its high resistivity. (See also; S Glass, Warp Glass)

Resins that may be of widely different structures but are characterized by the presence of the epoxy group. A polymerizable thermoset polymer containing one or more epoxide groups. The aromatic type epoxy resins are normally used in composites.  Epoxy Resin is primarily used with EPS foam although it can be used on Polyurethane Foam as well.

Expanded Polystyrene Foam also known as beaded foam.  Must be used with Epoxy Resin.  Comes in billet (block) or molded blanks.

Fake Balsa airspray artwork on a board that mimics the look of balsa wood.

A cloth woven from glass strands gathered into yarns, available in various weights and finishes. Fibers similar to wool or cotton fibers, but made from glass; sometimes called fibrous glass. Glass fiber forms used in surfboard making include cloth, milled fibers, roving. (See Also; E Glass, S Glass, Warp Glass, Volan, Roving, Milled Fiber)

Individual glass fibers of indefinite length, usually as pulled from a stream of molten glass flowing through an orifice of the bushing. A number are gathered together to make a strand or end of roving or yarn.

A relatively inert material added to reduce cost, to modify mechanical properties, to serve as a base for color effects, or to improve the surface texture.

Material applied to fibers, after sizing is removed, to improve matrix-to-fiber coupling. Typical finishes used for surfboard fiberglass fabrics include Silane and Volan.

A circular separation, typically in a gloss coat generally caused by contamination such as oil, dust, water, or stearate sandpaper. The term “fish eye” is also sometimes applied to dimples in gloss coats caused by failure of wax to rise to the surface.

Flash is a process done during the Hot coat/Sanding Coat when using UV cure resin.  Once the UV Sanding Resin is brushed on the board it should be taken into the sun for approximately 20 seconds max. Then brought back into shop out of direct sunlight . This Flash to the sun activates the UV curing process helping the wax to come to the surface.  Once you see the wax on the surface of the board it can go back into the sun for a complete cure.

A fin designed to bend, usually at the tip, to enhance performance.

A lightweight, cellular plastic material containing gas-filled voids. Surfboard foams used by surfboard makers include polyurethane (most common), expanded polystyrene (EPS), extruded polystyrene (XPS, XTR), and Styrofoam (which is a brand name polystyrene).

Foil is the change in thickness of a board from the nose to the tail, or of a fin from the leading edge to the trailing edge. (See Also; S-deck)

This is a method in laminating a board where you freely lap your cloth over the rail onto the opposite side of the board. This method works best when your cloth is cleanly trimmed for an even lap throughout the board.

FUMED SILICA (trade names Aerosil , Cabosil)
A very low weight thickening agent used in polyesters or epoxies.

Time from the introduction of a catalyst or hardener until gel formation (i.e. the stage at which a liquid begins to exhibit pseudo elastic properties).

The amount of glass by weight compared to the amount of resin by weight in a finished laminate.

Resin formulated to provide a hard durable glossy finish coat for surfboards. Can be wet sanded and polished to a brilliant finish. Contains wax, polymers, and dries tack free.

Increase or break in template curve, similar to kick. Usually within 2 feet of tail.

A fixture for holding parts in position, while joining them together or to maintain their shape.

Fabric of non twisted yarn, flat weave and direct sizing, improved physical properties and excellent clarity. K Glass is somewhat more challenging to laminate.
Increase or break in rocker curve; usually within 2 feet of nose or 1 foot of tail.

When resin starts to gel and harden.

1) (verb) The act of processing resin and reinforcement into a bonded structure, as when one or two layers of fiberglass cloth are laminated onto a surfboard blank,
2) (noun): A product made by bonding together two or more layers (plies) of material.
3) a symbol, logo, decal or artwork [aka “lam art”] that is typically printed on rice paper and laminated onto the surfboard under or between the fiberglass cloth layers.

Resin that has no wax added and is used to attach (laminate) fiberglass cloth to foam, wood or other fiberglass.

A lap is an area of overlapping fiberglass cloth, typically along the rails, nose and tail of a surfboard. When the overlapping cloth is left alone it is called a free-lap. When the overlapping cloth is trimmed or cut along a tape-line so that it looks neater, it is called a cut-lap. Laps should be sanded down to be flush with board before final glassing.

Safety information required by federal regulation; applicable to e.g. fiberglass fabrics, resins, solvents. The MSDS provides important information regarding health hazards, flammability, special protection required, first aid procedures, etc.

Methyl Ethyl Ketone Peroxide, a catalyst used to cause polyester resins to harden. Highly corrosive; a strong oxidizing agent (free radical source). Available in regular or slow reaction (MEKP/SR)

Microscopic bubbles of glass, ceramic or Phenolic, used as fillers in epoxy and polyester compounds to reduce density.

Halfway between the nose and tail of a surfboard. Often the wide point is described as being so many inches in front of, or behind the mid-point.

Continuous glass strands hammer milled into very short glass fibers. Fine powdered glass fiber used as reinforcement to increase mechanical strengths of resins. Often used with microspheres. Milled fiber is used to add strength, e.g. when putting leash plugs or fin plugs in a surfboard. Can make sanding difficult.

A simple molecule that is capable of reacting with like or unlike molecules to form a polymer. E.g., Styrene.

Rocker inherent in any given blank, i.e. the rocker that is molded into the blank, as intended by the designer. Natural rocker can be customized when stringers are glued in by bending [e.g. the nose a specified amount higher (+N) or lower (-N), or by adjusting the tail similarly (+T, -T)].

The width of the nose (front) end of a surfboard, always measured 12” back from the tip of the nose.

Laying down additional laminating resin on laps, rails, tail, or low spots before a hot coat to ensure that all weave is covered.

An extra layer of fiberglass cloth added to a portion of the deck of a board, either under the knees (knee patch) or under the back foot (tail patch) – used to add strength and reduce dents. Sometimes added on the bottom of the board around the fin box area.

A color additive put in resin to produce a solid or opaque color. Pigments contain solids, and can be used to make a resin opaque. The higher the proportion of pigment, the more opaque the resin. The only pure pigment is white. When adding pigments to Epoxy best to add it to the Hardener side first. (See Also; Tint)

Lines made using heavily pigmented resin, rapidograph pens, or painted on, used for decorative purposes or to cover areas such as lap lines.

Traditional resins used with Polyurethane foams.  Polyesters are thermosetting resins, produced by dissolving unsaturated, generally linear, alkyd resins in a vinyl-type active monomer such as styrene, methyl styrene, and diallyl phthalate. Cure is affected through vinyl polymerization using peroxide catalysts and promoters, or heat, to accelerate the reaction.

A large molecule created by a large number of smaller molecules, called monomers, in a regular pattern. The word polymer comes from Greek roots: poly means “many” and mer comes from “merous” which roughly means “parts”.

The traditional Surf board foam made famous by Clark Foam.  An organic polymer used to, make surfboard blanks, formed by reacting a polyol (an alcohol with more than two reactive hydroxyl groups per molecule) with a di-isocyanate (such as MDI, or methylene diphenyl di-isocyanate, or TDI, or toluene di-isocyanate) in the presence of suitable catalysts and additives.

“Silcell” also known as “Q-Cell” is a filler added to resin typically when doing ding repair, used to thicken. Tends to be slightly gray in color. See Cabosil, microballoons, milled fiber.

On a fin, rake is the angle off of vertical of the leading edge of the fin. A highly raked fin tends to stall or spin out sooner, other things being equal.

Rails are the edge of a surfboard. Soft rails are relatively round and without defined edges. Hard rails have a corner and a distinct edge. The shape of the rails affects how water flows over the rails. Boxy or rounder rails are usually associated with beginner surfing or non-high performance, thus they are more forgiving.  On the contrary the hard or knifey rail is associated with high performance surfing.

Cuts (typically “V” shaped notches) put into fiberglass fabric before laminating. The purpose of a relief cut is to allow fabric to go around the nose, tail, tight rails, and corners without “bunching up.” If Relief Cuts aren’t correctly applied the result most often will be air/poor lamination causing the need to Backfill to avoid Sand Throughs.

In reinforced plastics, the material used to bind together the reinforcement material; the matrix. Most resins are polymers.

Face mask used to avoid inhaling particles and vapors. 3M makes good ones that use organic vapor cartridges for glassing and particulate filters for sanding. Make sure it fits!

Paper used for laminating artwork into surfboards. Nearly invisible when laminated.

Rocker is the bottom curve of a surfboard from front to rear. Entry or nose rocker is the part of the curve under the front of the board; tail rocker is the curve under the back of the board. The rocker is typically measured along the stringer; rocker measured at the rails can be different due to vee, belly or other bottom contouring.

A collection of bundles of continuous filaments collected into a parallel bundle either as untwisted strands or as twisted yarns. Used to install glassed-on fins, also known as Fin Rope.

An S-deck is a hump or dome in the middle to rear area of the deck, as opposed to an even curved deck which is flat across. S-decks are usually domed both ways lengthwise and laterally. Using an S deck is a way of adding volume.

A family of magnesium-alumina-silicate glasses with a certified chemical composition which conforms to an applicable material specification and which produces high mechanical strength. Compared to E-glass, S laminates show improved tensile strength, flexural strength, flexural modulus and compressive strength, impact resistance and toughness. S glass laminates are about 10% to 30% stronger than E-glass laminates, for the same weight.

Laminating Resin that has Surfacing Agent  (S.A.) added and is used to as a Filler Coat after the board has been laminated. Can be purchased as Hot Coat/Sanding Resin or can be mixed at home. Standard mixing ration is two times the amount of MEKP for S.A. See Surfacing Agent

Process of using Hot Coat Resin as a Filler Coat after the board has been laminated.  The Sanding Resin is catalyzed then brushed over the laminated cloth to fill the weave.  Ideally most of the Sanding Resin is sanded off in the sanding process but the goal is not to sand the cloth.  Once the resin heats up, goes off, the wax comes to the surface making the resin sandable. Resin contains Surfacing Agent (wax).  Also known as Filler Coat and Hot Coat.

The length of time a material can be stored and continue to meet specification requirements, remaining suitable for its intended use.

A compound that binds together and stiffens yarn, providing resistance to abrasion during weaving; normally removed and replaced with finish (e.g. Volan, Silane) before use.

A liquid used to dissolve and clean materials. Acetone (polyester resin) and Mineral Spirits (Epoxy Resin) are two types of Solvents.

A double sided template with the outline from the nose through the center of a shape on one side of the template, and the tail through the center of the board on the other side. The name comes from the way you trace out one side, then spin or flip the template to continue tracing out the rest of the board.

A concave area cut into the deck. On longboards it is usually in the front third of the board to reduce weight. In kneeboards, the entire deck may be concave. In extreme cases the entire deck is eliminated so the kneeboard can flex to enhance performance.

External or internal cracks caused by tensile stresses; cracking can be present internally, externally or in combination.

A stringer is one or more strips of strengthening material, typically wood, glued vertically into the foam of a surfboard blank (i.e. basswood, spruce, balsa, red cedar, redwood). (See Also; T-Band)

An unsaturated hydrocarbon used as a co-reactant diluent (a thinner) for polyester resins. Polyester resins are combined with fiberglass cloth to laminate over polyurethane foam blanks to make surfboards. The addition of styrene monomer can reduce physical properties and affect cure times.

A styrene wax solution used to cause polyester resin to cure tack free. Must be added to a non-waxed resin to enable sanding. S.A. allows the surface of polyesters to cure. It limits adhesion of another coat of resin if the first is thoroughly cured. It may be removed by sanding. S.A. is added to polyester Laminating Resin to make Sanding Resin (See Sanding Resin).

Stringers glued together to form a strong laminate.  Sometimes used ornately and sometimes for strength.

A condition in which a plastic material can be dented with an inert object without sticking to it. It is indicative of a definite stage of hardening.

A block, typically of layers of wood or glass, attached to the tail of a surfboard. Protects the tail and used for aesthetics.

The width of the tail (rear) end of a surfboard, generally measured 12” up from the tip of the tail.

1) The template or plan-shape is the outline of a surfboard viewed from overhead, with the nose at the front, rails down the side, and tail at the back.
2) Templates are used for the initial outlining of a foam blank by marking out the desired outline, which is then cut out of the blank. Templates are often made of thin plywood or Masonite and can be reused many times (a throw-away template can be made of cardboard or even paper). Templates can be combined in different ways and/or used like French curves to “connect the dots” on new outline. (See Also; Spin/Flip Template)

A color additive put in resin to obtain a transparent or translucent color. Tints do not contain solids, and their use results in a resin that is translucent. The intensity of the color is raised by using more tint in the mix. Ideally added to the Hardener Side of Epoxy. (See Also; Pigment)

Toe-in is the angle of the fin relative to the stringer (i.e. the front of the fin is closer to the stringer than the rear of the fin). A single fin has no toe-in, as the stringer and fin are pointed dead ahead. Some (but not all) side fins have toe-in. E.g. A traditional fish has no toe-in because the fins are parallel to the stringer. Side fins on thrusters, twinzers, twin fins (other than traditional Fish) and quads are usually toed-in a small amount (1/8 inch to ¼ inch or so).

ULTRAVIOLET (abbreviated UV)
Ultraviolet or UV light is electromagnetic radiation in the part of the spectrum between visible light and X-rays. These wavelengths of light (100-400 nm, which includes UVA, UVB and UVC) cannot be seen by the human eye BUT are very bad for your eyes.Ultraviolet catalysts can be mixed with resins, which then cure when exposed to UV light. Brand names of pre-mixed UV resins include Solarez and Suncure. (See Also; UV Cure Resin)

UV Cure Resin: A mixture of polyester resin with a solar-activated catalyst. UV Cure resin will remain liquid until exposed to direct sunlight and hardens in approximately 3 minutes once exposed to sunlight. Can also be catalyzed using MEKP. (See Also; Ultraviolet)

An angle in the bottom of a surfboard breaking off from the stringer to the rails.  It looks like a V shape when viewed from the front or rear of the surfboard.

A laminating resin that is processed much like polyester, but has cured properties similar to some epoxy resins.

Carbon-containing chemical compounds (e.g., solvents or liquids) that evaporate readily at ambient or process temperatures. Environmental, safety and health regulations often limit exposure to these compounds, making low VOC content is preferable.

Also known as CHROME FINISH (VOLAN ‘A’) due to presence of chromium. Applied to glass fibers to give good bonding to polyester and epoxy resins. A sizing or finish applied to fiberglass fabric during the manufacturing process. If used with no pigments, volan cloth will appear to have a slight greenish, coke-bottle, tint. Volan boards typically have cut laps as free laps would show and be unattractive. Standard Volan finish is compatible with polyester, vinyl ester and epoxy resins. Volan laminates tend to dent rather than crack. (See Also; Silane)

Fiberglass woven with more yarn in the warp (length) direction for the purpose of added stiffness and buckling resistance. (Yarn in the other direction is called fill or woof).

To fill with resin; the condition of an impregnated fabric or roving when substantially all voids between the strands are filled with resin.

The widest single point on a surfboard, measured from rail to rail, across the stringer. Not necessarily the same as the midpoint, which is simply halfway between the nose and the tail.

Also known as a bump, or stinger. A wing is a point on the rail that sticks out noticeably from the rail behind it (closer the rear of the board).

The time during which a liquid resin after mixing with catalyst and/or other compounding ingredients remains usable. Also known as pot life.

Continuously twisted fibers or strands used to weave fabrics, e.g. fiberglass.

Save & Share Cart
Your Shopping Cart will be saved and you'll be given a link. You, or anyone with the link, can use it to retrieve your Cart at any time.
Back Save & Share Cart
Your Shopping Cart will be saved with Product pictures and information, and Cart Totals. Then send it to yourself, or a friend, with a link to retrieve it at any time.
Your cart email sent successfully :)