The art and science of wood veneer

The art and science of wood veneer

Veneer consists of a thin leaf of wood applied with glue to a panel or frame of solid wood. The art of veneer developed with earliest of civilizations. The story of hardwood plywood and veneer goes back as far as when the pharaohs ruled Egypt. During that era nearly 4,000 years ago, ancient Egyptians of the Nile Valley used remarkably durable cedarwood to build houses, palaces, temples, and fleets. The earliest historical evidence of of veneering is in a pictorial mural unearthed by archaeologists in Egypt. It is a known fact that ancient Egyptians built furniture with plywood. Mummies were entombed in a plywood sarcophagus case with an elaborately decorated veneer. Two thousand years ago, Cleopatra presented Julius Caesar with a veneered table richly decorated with inlays. Chinese, Greek, and Roman cultures all made early users of veneer and plywood.

Most people fail to understand that veneer is real wood! It is a thin slice of wood cut from a log with a special slicing, peeling, or sawing machine. Veneer is used for decorative and architectural purposes on plywood, particle board, fine furniture, and laminated shapes.

To prepare a log to be cut into veneer, it is steamed or soaked in a bath of very hot water so that the wood is more pliable. This “cooking” process will soften the wood fibers so that the veneer can be sliced without tearing and splitting the material. After the veneer is sliced, it’s pressed flat between heated metal platens and bundled into stacks in the same order that it was removed from the log. Using wood veneer opens a whole new world of woodworking to even the most inexperienced craftspeople.

By using exotic veneers, even simple woodworking projects can be turned into magnificent works of art. Veneer gives you a unique opportunity to purchase with some of the most beautiful and exotic woods in the world for your projects in an affordable way. Veneer has several major advantages over using solid wood lumber that are very important. These advantages are responsible for the grown of the art of veneering in professional cabinetmaking and furniture design. With the right tools, knowledge and skills, veneering is relatively easy for the amateur cabinetmaker that can turn even the most basic design projects into heirloom quality masterpieces.

Wood Veneers – Benefits and Advantages

The following list is just a few of the benefits and advantages to using wood veneer:

1. Material Stability
   Some types of wood are very unstable in raw lumber form. For example, the random grain in burl wood is beautiful in appearance but extremely prone to warping and splitting. By slicing a burl log into veneer, movement and distortion of the burl wood is kept under control by the glue and stronger wood beneath the surface of the veneer. Even the most difficult exotic woods can be sliced into a veneer and used to make a visually stunning yet architecturally stable wood panel.
2. Wood Cost & Availability
   Many wood species are so rare and valuable that tjhey would be too costly in solid lumber form. There is a shortage of natural resources available in the worldwide market for exotic woods and an ever-increasing demand. This situation means that an exotic wood log is worth ten times or more what it was worth only 7 years ago. By cutting an exotic wood log into veneer, the square foot yield of material available to the world market is increased by over 4,000% or more. One exotic wood log makes more money if it is sold as veneer rather than if it is sold as solid lumber. This huge increase in value applies not only to simple straight grain wood but also to “figured” wood materials with very unusual grain patterns such as bural, tiger, birds-eye, wavy, and curly .
3. Design Practicality
   Veneer can be formed and curved into almost any shape and design imaginable. This means your furniture designs are not limited to simple, flat, square shapes. For example, a classic serpentine dresser has surfaces that are formed into a wavy shape rather than straight and flat. It is only makes good sense to use veneer for any curved woodwork designs. Oak, cherry, walnut, and other hardwoods plywood are considered indispensable for many woodworking projects.
4. Design Layout Options
   Using a few sheets of sequenced veneers glued together, you can create beautiful, exotic, artistic wood surface designs. You can learn more about cutting and bonding veneer to get a perfect seam by clicking here.

Public Perceptions of Wood Veneer

Unfortunately, most people think that products made with wood veneer are inferior or cheap. The average consumer in the USA and Canada believes that the main reason for using wood veneer to build furniture is because the manufacturer wants to save money. It is true that wood veneer furniture created before and after the second world war were not good quality. This is because there was a scarcity of skilled craftsman, glue and finishing materials available during those times. Even up till the 1970s, consumer products made with wood veneer were viewed as inferior.

After the 1970s, however, the quality of manufacturing materials used for woodworking dramatically improved. Amateur woodworkers began to take a new interest in wood veneers and manufacturers improved the quality of their designs. Design techniques which were once considered to belong to an exclusive group of skilled cabinetmakers became available for anyone to learn via Internet, at the library, or through specialized woodworking classes. The quality of veneer adhesives also dramatically improved as chemical engineers developed cheaper and more permanent bonding agents. By the early 1980’s, the science of wood veneer bonding agents had been nearly perfected. To accommodate the amateur cabinetmaker market, wood adhesive products have been designed to be affordable, durable, and easy to use.

Wood Veneer Grain Patterns

There are literally hundreds of types of different wood veneers available today. It is often made from species of trees such as cherry, oak, maple and birch, as well as rare and exotic trees such as Brazilian rosewood and eucalyptus. When veneer is applied properly to the base material, it gives the illusion that the entire piece is made entirely from the same type of wood as the veneer. There is a multitude of words to describe the unusual patterns found in exotic wood veneer. To help you make the right choice when you are purchasing your veneer, here’s a brief list of what you’ll find:

Quilted A “high-end” design pattern with rolling iridescence in distinguished clusters.		Burl One of the most popular design patterns; burls have circles of random cell growth		Spalted Otherwise called Ambrosia. Dark lines often caused by fungus or insects; very rare in veneer. Very outstanding design pattern.		Curley This design has cross-grain ripples that shimmer where cell orientation is uneven.
Crotch Has a very high shimmer; the veneer is sliced where the tree has forked into two directions.		Fiddleback A higher density of the same pattern found in curly woods; highly sought after by cabinetmakers.		Mottled Has angular rays of shimmer with sharp edges; high iridescence to create a bold design statement.		Birds Eye Dots of very dense wood cells. It is typically found in maple but can occur in other woods.
Quartersawn This is a type of saw cut not a natural wood pattern. The material is sliced to yield a very straight grain; some veneer species such as oak show shimmering flecks of light.		Flat Cut This is a type of saw cut not a natural wood pattern. This traditional cut creates a “cathedral” types of grain to the wood which is often compared to the look of solid lumber.		Pommele Is pronounced ‘Pom-el-ay’ and resembles rain drops cascading down a window. It has a very eye catching effect when finished.		Blistered Very similar to pommele but with a slightly larger pattern and less shimmer. It is common in sapele but very rare in other species of woods.

Important Information About Burl Veneers

Burl is considered my many to be the most elegant of of fine woods. They are knobby wart-like growths that grow naturally on the lower parts of various species trees. Nobody knows why they grow but some believe that the growth is caused by disease or damage to the tree during its early years. Every tree contains “dormant buds” that contains all of the genetic information neeeded to grow a new tree. When the tree is damaged, many of these dormant buds activate and grow to create a chaotic grain pattern that patches the damage. Just as a wound in a human can cause a scab to develop to allow a would to heal, a burl is is formed as a tree band-aid. If you’ve ever tried to split a burl with a wedge, while cutting wood you will know how strong the grain can be.

Burls veneers will show any one of three orientations in wood grain:

• Cat’s Paw Burl Grain

The most common type of grain is frequently referred to as the “cat’s paw” type because of the circles of grain that sit side by side. This design is the result of slicing the raw burl from the outside face of the veneer on a rotary slicing machine.

• Rays Burl Grain

The same material can also be cut to what appears to be “rays” of wood grain. This is done by slicing the raw burl from the side.

• Cluster Burl Grain

The cluster type of burl is sometimes considered a lesser quality veneer. For this material, the veneer has patches of burl grain which are rotary sliced from the log. These veneers can often be used to on projects where a true burl grain veneer would be too outstanding and a more subtle design is required. When a more subdued burl grain design is required for a project, cluster burl veneer will work well.

Types of Wood Veneer

There are different types of wood veneer. Each is designed to be used for a specific design application.

• Raw Wood Veneer

This is the most common type of veneer for exotic wood species and figures. It can be applied directly to a substrate material using cold press veneer glue and either a vacuum press or clamping press. If you prefer the traditional approach to laying veneer, raw wood veneer can be applied using hot hide glue and a veneer hammer. Raw wood veneers are considerably less expensive than the backed veneers. Unlike backed veneers, you can use either side of a raw wood veneer. They are available in practically every species and grain pattern type.

• Shop-Sawn Veneer

With a simple bandsaw properly set up, some woodworkers prefer to cut their own veneer from raw wood material. Hand made wood veneers are often thicker than mill-sawn veneers which has many advantages and disadvantages. To learn more, see the chart below.

• Backed Veneers

Wood veneers with a material backing on one side are usually available in large convenient sizes although they are not as widely available as raw wood veneers. Backing materials for wood veneer are designed to strengthen the veneer, add flexibility, and to make it easier to glue. Different types of backed veneers are available with foil, wood, or phenolic (flexible plastic) backing materials which are used for specialized applications. The most common are those which are backed with either paper or cloth. Paper backed veneers are usually available in 10 and 20 mil thickness.

This measurement is a reference to the thickness of the backing material, not the wood veneer face. In most professional shops, the 10 mil backed veneer is used on vertical applications and the 20 mil is used for horizontal projects. To apply a backed veneer, you can use a cold press veneer glue in a vacuum press for a very durable bond. Contact cement can also be used. Paper backed veneers are typically available in 4′ x 8′ sheets and consist of several veneers matched side by side to make up the full width.

Wood Veneer Cuts

The size of the log, the species of wood, the grain pattern desired and other factors determine which type of cut will be used to create raw wood veneer leafs. Below is a chart that shows some of the most common cutting techniques used.

		Rotary Cut The log is mounted centrally on a wood lathe and turned against a broad cutting knife like unwinding a roll of paper.
		Quarter Cut Slicing is done perpendicular to annual growth rings on the tree. This creates a straight or striped pattern.
		Crown Cut (1) Created by using flat sawed lumber rather than by using a round log. A variegated profile is created with this slice.
		Crown Cut (2) Created by slicing parallel to the center of the log. This also creates a variegated profile.
		Rift Cut This straight grain cut is made by slicing red or white oak wood at a slight angle to minimize grain irregularities.

Wood Veneer Matching Techniques

The following images show the matching techniques you can use to put together wood veneer strips or plates to form a single sheet or panel. Various wood types, colors and grain patterns are shown to give you some idea of the kind of design effect that can be created using this technique.The slices of veneer are always kept in the same order in which they are cut from the tree, and are known as flitches.

		Book Match Successive leaves in a flitch are flipped over like pages in a book and glued together. The result is a series of paired leafs since one leaf is the mirror image of the other.
		End Match One leaf is spliced end to end with another leaf to create a longer panel or piece of veneer. End matching is often used to extend the apparent length of available veneers.
		Quarter Veneers are matched in groups of four and then book and end matched. Works well with burls and crotches. The end result is a balanced square of 4 veneer figures.
		Random Match Random matching means you lay out the veneer without any matching at all. Works well with low grade veneer where leaves are varying width, grains and colour shades.
		Diamond Match This is done using straight grain veneer. The leaves are matched at an angle to the quadrant lines so that the grain forms a V. This results in a diamond shape formed by the grain directions.
		Herringbone Match Veneer strips matched to both sides of a center line with the grain at a 45 degree angle. The resulting appearance is reminiscent of the bones in a fish attached to the backbone.
		Slip Match Veneer is “slipped” and glued together lengthwise. The result is a series of grain repeats with no pairs. Getting grain patterns aligned together perfectly straight could be difficult.

Wood Veneer Sizing and Availability

Wood veneers are typically sold by the square foot. They can be sold in strips or as plates or “leaves” with matched material grain patterns. Veneers are manufactured for retail sales distribution in the following standard thickness size increments:

• 0.50mm (1/50″
• 0.55mm (1/46″)
• 0.60mm 1/42″
• 0.65mm 1/39″
• 0.70mm (1/36″)

Thicker sheets, strips or square leaves can be custom cut at home or may be available from veneer manufacturers as a custom order. With the ability to join veneers, even small pieces are usable, resulting in very little waste. Small packages of veneers which are sequence matched are available, and are perfect for small woodworking projects. You can order several hundred different types of wood veneer in full crate increments (flitches) at very competitive prices. It is also possible to buy plywood and other substrate materials with veneered faces for larger projects.