zhejiang rwoods strives to provide its customers with the finest, most consistent quality plywood available on the market. for this reason, schaller hardwood has chosen columbia forest products to be their producer of choice. columbia forest products, the nation’s largest manufacturer of hardwood plywood products, has developed a grading system that is "a standard beyond the standard".
the american national standards institute (ansi) developed the quality criteria for the grading of hardwood plywood. the ansi standards were meant to provide a system of guidelines to provide for uniform grading throughout the industry. these initial standards were a good start, however the standards set by ansi are so broad and general they allow for a substantial variation in quality from manufacturer to manufacturer. columbia forest products "a standard beyond the standard" is a grading system that tightens and improves upon the current ansi standards. "a standard beyond the standard" spells a guideline of exacting specifications for each grade and specie of hardwood plywood. columbia forest products "a standard beyond the standard" is a grading system that ensures consistency from shipment to shipment. by using plywood graded under this system you are assured of hardwood plywood that should look and perform the same panel after panel.
definitions of the different veneer cuttings
r/c—rotary cut—the log is centrally mounted on a computerized, hydraulic lathe and turned at a high speed against a special knife, which peels the veneer in a long continuous sheet, similar to unwinding a roll of paper. a wide variegated grain pattern is often the result. rotary cut veneer is either left as a whole piece veneer, or is cut into narrower widths to be assembled later into a spliced veneer face.
p/s—plain sliced—the log is cut into half lengthwise. the half log is then moved back and forth against a stationary knife, producing parallel slices through the center of the log. this produces narrow strips of veneer that closely match that of flat sawn lumber. the narrow strips of veneer are assembled later to form the veneer face.
rift sliced—rift sliced veneer is produced in much the same way as plain sliced veneer except that the log is cut into quarters lengthwise. the log is then sliced at a 90 degree angle to the grain. this produces narrow strips of veneer with a straight vertical grain. the narrow strips of veneer are assembled later to form the veneer face.
quarter sliced—quarter sliced veneer is produced in the same way as rift sawn veneer.
half round sliced—half round slicing is a variation of rotary cutting. in half round slicing the log is mounted off center on the lathe so only one side of the log is sliced at a time. this results in a veneer exhibiting characteristics of both rotary cut and plain sliced veneer.
veneer matching
whole piece face---this is exactly what it is. whole piece faces are made of rotary cut veneer. the whole piece face will not contain any splices. a whole piece face will give a continuous grain pattern across the entire panel.
spliced face---this is where the faces are composed of several pieces of veneer glued together to form a face. the appearance of a spliced face is determined by the way the veneer are composed.
book matched face---this is where the face is composed by turning over every other strip of veneer and joining them together. this produces a grain pattern that is matched at every veneer joint. the term book match refers to the veneer being matched just like the pages of a book.
slip matched face---this is where the face is composed by laying the veneer strips side by side and joining together to form the face. this produces a repetitive grain pattern.
description of hardwood plywood cores
hardwood plywood is manufactured using three basic components, a face veneer, a back veneer, and a core. there are four basic core types. veneer core, medium density fibercore, particleboard core, and lumber core. at schaller hardwood we also use a hybrid type core called classic core ii that incorporates the advantages of two different basic core types. a brief description of each follows:
v/c—veneer core—this is the standard veneer cross-banding technique where an odd number of veneers are laminated together to produce the final panel. the number of veneers in a panel is referred to as the number of plies. most hardwood plywood contains from 3 plies in ¼" plywood to 11 plies or more in the thicker panels.
mdf—fibercore—this is where a medium density fiberboard is used as the core in the manufacture of the panel. this is a three-ply construction using a face veneer, a back veneer and the fiberboard as the core. this type of construction tends to produce the most stable panel. fibercore construction also offers a void free core with excellent machinability. the fibercore with its super smooth surface provides a superior core for finishing the face and back veneer. the only real negative on fibercore construction is the weight of the panel produced. a typical ¾" thick plywood with fibercore will weigh approx. 100 lbs.
pbc—particleboard core—this is where an industrial grade particleboard is used as the core in the manufacture of the panel. the construction of the panel is the same as fibercore. particleboard core has the same advantages and disadvantages of fibercore with the exception of not having the same degree of machinability.
lbc—lumbercore—this is a five-ply construction made up of two face veneers, two cross-band veneers, and a solid lumber core. the core is usually made up of edge-glued strips of lumber 1-1/2" to 2" in width. the core is basically solid and free of voids, which give unusual strength and high resistance to buckling, twisting or warping. panel thickness is normally ¾".
classic core ii—this is a hybrid of veneer core and fibercore. the panel is constructed using a veneer core with the two cross-bands under the face and back veneer being a thin fibercore. this construction eliminates the problem of veneer telegraphing through the face veneer when finishing and produces a panel weighing considerably less than the fibercore. at schaller hardwood, we have found this type construction best used on any of the fancy wood panels (cherry, walnut, white oak, etc.)
explanation of hardwood plywood grades
hardwood plywood uses two alphanumeric characters to designate the grade of the panel. the first character refers to the quality of the face of the panel. this character is normally a letter-such as "a", however in special production products it could be a number. the second character is normally a number and refers to the quality of the back panel, however in special production products it could be a letter. a typical plywood grade would be a-1. this means that the plywood would have an "a" grade face with a "1" back. a-1 and b-2 plywood grades are typically the grades most often used in ½" and thicker panels for cabinet work. the most common grade used in ¼" panels is a-4. this means that the plywood will have an "a" grade face with a "4" back. a brief summary of the specifications of each face grade and back grade follows, along with a comparison chart of columbia forest products "a standard beyond the standard" and ansi grades. schaller hardwood lumber company in an effort to provide the very best for our customers and their clients, stocks an a faced panel in all thickness of plywood.
a-grade face—an "a" face on hardwood plywood should be matched for both grain and color. all veneer splices should be book-matched for a visually pleasing appearance. there should not be any abrupt changes in color or grain between the splices. an "a" face will not permit sound knots, repaired knots or rough-cut veneer. an a face may allow slight mineral streak and/or vine marks. the number of defects such as pin knots or small burls varies according to the specie of veneer. this is the best face grade on plywood normally stocked and is often used for upper-end cabinetry, architectural millwork, and quality furniture.
b-grade face---a "b" face on hardwood plywood should be matched for a pleasing color, but not necessarily for grain. "b" grade faces are generally very similar to "a" faces, but do allow some sound or repaired knots and some slight rough cut veneer. "b" grade faces will also allow slight mineral streak and vine marks. "b" grade faces are, often used by customers wishing to save a little money on plywood. many suppliers offer the "b" grade faces in lieu of "a" grade faces in an effort to be more price competitive. comparing the price of "a" grade faces and "b" grade faces is not comparing apples to apples. always be sure to specify the face grade of plywood you are wishing to receive.
c-grade face—a "c" face on hardwood plywood allows for unlimited pin knots and small burls. a "c" face can also contain repaired knots and sound knots. the "c" grade will also allow unlimited mineral and vine marks. a "c" face should be a sound smooth face. a "c" face is used primarily on paint grade type panels, in lower-end case work, and for cabinet interiors in upper-end cabinetry.
d-grade face---a "d" face on hardwood plywood is similar to the "c" face, but will allow some rough cut veneer and a few more repaired and sound knots.
1 back—can contain up to 16 sound tight knots not exceeding 3/8"
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