Types of Veneer Cuts:
The method in which veneers are cut is an important factor in producing the various visual effects. Two logs of the same species, but with their veneers cut differently, will have entirely different visual characteristics.
In veneer manufacturing, five principle methods of cutting are used: rotary, flat slicing, quarter slicing, rift-cut and half-round slicing.
|The log is mounted centrally in the lathe and turned against a razor sharp blade, like unwinding a roll of paper. Since this cut follows the log’s annual growth rings, a bold variegated grain marking is produced. Rotary cut veneer is exceptionally wide.||The half log, or flitch, is mounted with the heart side flat against the flitch table of the slicer and the slicing is done parallel to a line through the center of the log. This produces a variegated figure.||The quarter log or flitch is mounted on the flitch table so that the growth rings of the log strike the knife at approximately right angles, producing a series of stripes, straight in some woods, varied in others.||Rift cut veneer is produced in the various species of Oak. Oak has medullary ray cells which radiate from the center of the log like the curved spokes of a wheel. The rift or comb grain effect is obtained by cutting at an angle of about 15% off of the quartered position to avoid the flake figure of the medullary rays.||A variation of rotary cutting in which segments or flitches of the log are mounted off center in the lathe. This results in a cut slightly across the annular growth rings, and visually shows modified characteristics of both rotary and plain sliced veneers.|
What is Veneer?
Veneer is a thin layer of wood of uniform thickness produced by peeling, slicing, or sawing logs, bolts, or flitches. The art of veneering is nearly as old as civilization itself. Exquisitely designed and skillfully crafted pieces of furniture with exotic veneer inlays and plywood components found in the tombs of Pharaohs are testimony to the lasting value of one of nature’s most reliable natural resources – hardwood.
The designer is as sensitive to his material as any sculptor or painter. Full expression of his design depends on the species of wood selected.
Certain species, selected for strength rather than beauty, are generally used for inner layers of hardwood plywood. They are often rotary cut. The veneer is peeled off the log in continuous sheets as wide as the length of the log.
For the production of face veneer, logs are selected according to size, figure, color and natural character marks. Cutting, the central operation in a veneer factory, takes place on a vertical slicer or on a half round rotary, depending on the species and the special grain character desired. Both systems produce veneer sheets collected in consecutive order no wider than the diameter of the log.
Face veneers are manufactured in much thickness depending on the end use and customer’s requirements. They are normally available from 1/16″ to 1/125″ (1.7 mm to 0.20mm). Modern technology in veneer slicing and usage has enabled furniture and panel manufacturers to successfully use thinner veneers, thereby helping conservation of hardwoods.
After cutting and curing to obtain the desired color, the veneers are dried, sampled and packaged for storage or shipment. The buyer looks at representative sheets from many flitches. He then makes his selection according to his individual needs taking into consideration figure type, color, price and yield.
Constant research is going on to improve veneer manufacturing processes, adhesives, sanding methods and wood finishes. Wood technologists, engineers, chemists and designers are working to improve an already superior product, hardwood plywood.