Is That Veneered?
The earliest veneer to be used in furniture was 3,000 years ago in Egypt. These early cabinetmakers used bronze handsaws to cut thin slices of rare wood for veneering and inlaying their furniture. It was a process that wasn’t to change until the 19th century, when the circular saw replaced the laborious task of hand-cutting veneer. Otherwise the art of veneering didn’t really change until the 20th century with the introduction of synthetic resin glues.
Some people still think that veneer is cheap work covering up inferior wood or craftsmanship.But in the 1830s ,when veneer was replacing carving as a way to ornament furniture, the cost to veneer was equal to the cost of carving. The ground wood to be veneered had to be straight and knot free. The craftsmanship had to be done right for the veneer to last. Not until the early 20th century did veneering gain a bad reputation. The main culprit was factories that used contaminated hide glue, which broke down sooner than normal.
Veneer is produced by three different methods sawn, sliced, or rotary peeled. As mentioned before, hand sawing was the earliest method of cutting veneer. This could be done by two men and a frame saw. Small logs were stood on end and secured in a vice. A man on either side cut down through the log with a large frame saw to produce the veneer. This was cut as thin as 1/64 of an inch or thinner by hand. In the early 19th century large circular saws up to 18′ diameter replaced hand cutting. This was the first use of circular saws.
In 1806 a machine was introduced that sliced the log into veneer. This was much like a paper cutter, except the log moved past the knife. It produced very thin slices with no waste. With saw cutting, as much wood had been wasted as was sawn off, due to the saw kerf. This process allowed an abundance of crotch mahogany to be used on furniture
Rotary peeling began being used by the latter part of the 19th century. It allowed a whole log to be peeled without a break in the veneer. The process is similar to slicing, but produces a much larger sheet of veneer. This made the manufacture of plywood possible. Cabinetmakers had been making small pieces of plywood in the 18th century for use in delicate mirror frames.
With either sliced or rotary veneering the logs are soaked in vats of water to make the wood more pliable as they are cut. After drying the sheets of veneer are ready for use.
When the slices come off the log, the sheets are stacked in the same order they were taken off. This package is known as a flitch. When a cabinetmaker opens a flitch there are several patterns that can be produced with the veneer. Since only the rarest and finest logs are selected for veneering, the figures are bold and decorative. The sun burst, book match, slip match, butterfly wings, diamond, and many more patterns can be found in the flitches. In the 18th century, fewer of these patterns were used because of the difficulty of joining the thicker sheets of hand sawn veneers.
To adhere the veneer to the ground work glue is used. Before about 1820 fish glue was used in cabinet shops. Hide or Scotch glue came into use early in the 19th century. Both of these glues need to be heated when used and the wood warmed by a fire before glueing. In the past, wood shavings were set ablaze in a brick enclosure and the work was warmed.( This may have been the cause of the fire that destroyed Thomas Chippendale’s shop.) Cauls slightly larger than the veneer were warmed, as well. These were clamped on top of the work to keep the glue warm and put pressure on the veneer as the glue set. Modern resin glues, have eliminated the need and the danger for warming the work. They are not destroyed by bacteria or affected by water, and have a longer working time.
Pressure must be applied as the glue sets. This can be done with clamps, in a veneer press, or by hammer. Small pieces can just be clamped; larger work needs one of the other methods. Hammering is done by a T- shaped hammer, worked across the surface of the veneer in zigzag motions as the hide glue cools. Pressure of the hammer is started in the center of the work and moved to the outer edges to squeeze excess glue out. This is done very quickly, as the glue grabs while cooling
Veneer presses are made of frames called stations. These are heavy timbers of wood with spacer blocks in between so the work can be placed inside. The top timber has several heavy screws that when tightened,apply pressure to the work. Throughout history it was difficult to get even pressure over the entire work surface. But today, a new press uses air pressure to even out the pressure over the surface. This is done with a heavy plastic bag and a vacuum pump. Much like the old press, cauls are still needed, but once a vacuum is drawn, up to 1,200 pounds per square foot is applied to the veneer. Thisequates to parking a Volkswagen on every square foot of the work. When the glue has set, one is sure the veneer is flat and will stay in place for years to come.
Veneering is an excellent way of decorating furniture with rare exotic hardwoods while at the same conserving their use. With new glues and presses, one can be assured of the durability and lasting beauty of veneered furniture. Even with these advances, a cabinetmaker from centuries past would still recognize the art of veneering in a shop today.
Leave a Reply