Chapter 13

Manufactured Panel Products

Manufactured Panel Products

• Wildly used to create large surfaces for case goods– Reduces the need for edge gluing– More stable than • Warp less• Dimensionally stable

• There is not continues grain pattern

3 Categories of Panel Products• Structural Wood Panels

• Appearance Panels

• Engineered Board Products

Structural Wood Panels

• Selected when Strength and stability are required– Roof, Wall, Floor.. Building Construction

• Plywood– Made by bonding layers of wood veneer with

adhesives• Orient Strand Board (OSB)• Wafer Board• Structural Particle Board

Plywood

• Most common structural panel• Veneers are cut in a lathe – Rotating a

Debarked log• Face Veneers are applied over the core

material• Pound for Pound plywood is stronger than

steel, unlike solid wood that strong along the grain and weak across the grain

Veneer-Core Plywood

• Plywood – Made by 3-5-7-9 layers of veneer depending on

the desired properties.– The thickness of the layers and the number of

cores equals the overall thinness• Panel thinkness varies from 1/8” to 1 3/16”– 3 ply panels are often ¼” Thick– 5 or 7 plies are used for ¾”

• f

Veneer-Core Plywood• This type of construction is composed of an odd number of veneer plies. The middle ply is called the

"center" and plies on either side of the center but beneath the outer plies are called cross bands. Outer plies are called "faces" and "backs." Panel thicknesses are available from 1/8" to 1-1/2";1/4" or thinner. Panels are normally 3-ply; thicker panels are 5 to 11-ply or more.

Venner Core• A common word hear by woodworkers is veneer. All it means is a

thin sheet (fraction of an inch) of wood cut from a log. A veneer can be cut from almost any type of natural wood/lumber. The veneer is what you see and it provides the visually impact of a solid wood - but you never know what is on the inside (core) unless you saw into it.

• A veneer is always attached to another product (usually an engineered wood) via a manufactured process involving adhesive, heat, and compression.

• Veneer-core plywood is only one option for cabinet work. Manufacturers also turn out a variety of panels with engineered-wood cores: medium-density fiberboard (MDF), particleboard, oriented strand board and even panels that combine engineered wood with solid-wood plies.

Lumber-Core Plywood• Lumber edge glued into a solid slab is

considered Lumber Core. Lumber Core plywood is most often found in the construction of import panels, usually only 18mm thickness panels.

• Lumber Core plywood consists of a face & back veneer, then a layer of crossband veneer, with the edge glued lumber in the center.

• Lumber Core plywood should be used for the bending strength and screw-hold ability.

• The ability of Lumber Core plywood to bounce back makes it an excellent choice when constructing long or wide shelves in cabinets or closets.

Lumber-core Plywood

Limber Core Plywood• This type of construction is usually 5-ply consisting of a face and back veneer, two

cross-bands and a core composed of strips of lumber edge glued into a solid slab.

MDF Core Plywood• The face and back veneers are applied directly to a core of (MDF) medium density

fiberboard. This type of panel construction is the most stable of all plywood.

MDF Fiberboard• Medium Density Fiberboard Core has the most uniform thickness and consistency

of any panel core. The face and back veneer are glued directly to the MDF Core without the need for a crossband veneer. The consistency in thickness and flatness makes MDF Core panels the preferred choice for 32mm construction.

Particle Board Plywood• The Face and back veneers are applied directly to a core of particleboard.

Particleboard Core Plywood

• Particleboard Core panels are constructed similar to MDF Core panels, with the face & back veneers glued directly to the core. Particleboard Core lays flat like MDF, but does not have the screw-hold strength of other cores. Particleboard Core is the least expensive of all core types.

Combination Core Plywood• There are two types of

Combination Core construction. The first type consists of a center veneer core and a crossband veneer on both sides of the center with a layer of MDF, particleboard, or hardboard under the face and back veneer.

• The second type consists of an oriented strand board or wafer board center with a veneer crossband on both sides, under the face and back veneer. Combination Core can be used when the project calls for consistent flatness and good screw-hold ability, without the weight of a MDF or particleboard core.

• A) MDF core is heavy and flat. Plywood with a core of medium-density fiberboard offers a smooth outer surface.

• B) Veneer-core plywood. This 3/4-in. veneer-core plywood is made from five internal plies laid at right angles to each other plus two thin outer veneers.

• C) Particleboard is another choice for an engineered core. A particleboard-core panel weighs roughly the same as MDF core, but it is slightly less expensive.

• D) Combined-core plywood is a compromise. Two layers of MDF and a center of wood plies make for a smooth surface and a strong, flat panel.

Adhesives

• Type 1 – Fully water proof adhesives– Exterior Plywood– Siding and sheathing

• Type 2 - Moisture resistant adhesives– Interior Plywood– Moisture content will not exceed 20%

• Type 3 – – Retain Strength– No moisture

• Urea Resin – Interior Plywood– Inexpensive – Flexible – Excellent Bond

Oriented Stand Board - OSB• 1) Tight construction and high strength

2) Minimum twisting, delaminating or warping3) No rotten or decay, strong against corrosion and fire4) Water proof, consistent when exposed in the natural or wet environment5) Low formaldehyde emission6) Good nailing strength, easy to be sawn, nailed, drilled, grooved, planed, filed or polished7) Good heat and sound resistant, easy to be coated8) According to Canadian Industrial Standard and Canadian OSB

OSB• Oriented strand board (OSB), first developed in the

1980’s, is a wood panel that has been “engineered to perform” for housing and construction. OSB is not chipboard, flakeboard, particleboard, or aspenite. It has been specifically designed to be the most dependable, versatile, and environmentally efficient wood panel on the market today. OSB uses only freshly harvested trees from sustainable fast growing forests or tree farms. T

• he trees are processed into precise strands averaging 4 inches long and 1 inch wide. The strands are oriented length-wise on the exterior and cross-aligned on the interior. The alternating layers are then bonded with resins under high heat and pressure. The resulting product is very strong and uniform and shares many of the same properties as plywood. Because of its great versatility and performance, we have chosen OSB in all areas of our homes where strength, stiffness, and durability are required.

Hardwood Plywoods• HARDWOOD PLYWOOD Description: Veneers (softwood or hardwood) glued in

layers with alternating grain, and covered with hardwood veneer. Uses: The traditional sheet good of choice for everything from furniture and cabinets to wall paneling and boxes.

• Available Sizes: 1/4", 1/2", and 3/4" are most common. Occasionally, you'll find 1/8", 3/8", and 5/8" in some species.

• Common Grades: Face: AA, A, B, C/D/E, Special. Back: 1, 2, 3, 4. Core: J, K, L, M. Panel types: Technical type, Type I, Type II (Type II most common for interior use.)

• Pros: More stable and less expensive than solid wood, widely available, made in a variety of species, and with many choices for veneer matching on faces.

• Cons: Thick sheets are heavy, exposed ply edges may mean you'll have to band with solid wood, thin face veneers (1/32") are easy to sand through and damage. Where to find it: Home centers carry a few species, such as oak, birch, maple. Turn to building suppliers and hardwood retailers for other species.

• Price (3/4"x4x8', sheet unless noted): $35 to $100+. Prices vary greatly due to species, face and back grades, ply count, and cut of veneer. A/2 or B/2 is reasonably priced and suitable for furniture.

Face Veneer

Face Veneer

Plywood Paneling

Fiberboard