Natural Birch Faces May Vary From All White to All Dark
The examples shown here are of typical grain and color variations found within “A” grade (book matched) rotary cut natural birch veneer. Again, they do not represent the widest range possible. Rotary natural birch is also available in “B” grade (pleasing matched) with the face made up of veneer leaves from different logs.
A close-up reveals the grain
pattern in a rotary cut natural birch veneer.
How Individual Veneer Pieces are Matched
Running Match: Non-symmetrical appearance in any single door face. Veneer pieces of unequal width. Each face is assembled from as many veneer pieces as necessary.
Balance Match: Symmetrical appearance. Each face is assembled from pieces of uniform width before trimming. This match reduces veneer yield.
Center Match: Symmetrical appearance. Each face has an even number of veneer pieces of uniform width before trimming. Thus, there is a veneer joint in the center of the panel, producing symmetry. This match reduces veneer yield.
There are basically four types of matches that are normally specified for door veneer faces, three of which are illustrated here.
Book match is the most common in the industry. In this method, every other piece of veneer is turned over so that adjacent pieces are opened like adjacent pages in a book. The veneer joints match and create a mirrored-image pattern at the joint line. This method yields a maximum continuity of grain. Book matching is used with rotary, plain sliced and quarter cut veneers. However, it is important to note that because the “tight” and “loose” faces alternate in adjacent pieces of veneer, they may accept stain differently, yielding a noticeable color variation. This so-called barber poling can be minimized by proper sanding and finishing techniques.
Slip match involves placing adjoining pieces of veneer in sequence without turning over every other piece. The grain figure repeats, but joints won’t show mirrored effect. Slip-matching is often used in quarter cut veneers to eliminate barber pole effects. It may, however, cause a sloping appearance of the veneer, especially in larger veneers.
Random match consist of selection of individual pieces of veneer from one or more logs. It produces a “board-like” appearance and is commonly used in opaque finish grades.
Pleasing match (not illustrated here) consists of a face containing components that provide a pleasing overall appearance. The grain of the various components need not be matched at the joints. Sharp color contrasts and the joints of the components are not permitted.
Plain Sliced and Rotary Cut Natural Birch
“Natural,” when referring to birch face veneer, indicates that the face may contain both heartwood (the red portion of the log) and sapwood (the white portion) in unrestricted amounts. Thus, natural birch faces may vary from all white to all dark, or any combination of white and dark. Also, the resulting grain configuration from book-matched plain sliced natural birch may appear as alternating strips of white and dark veneer. If you prefer a lite colored wood, specify white birch (all sapwood). If you want dark colored wood, specify red birch (all heartwood).
The grain pattern for rotary cut birch presents a more bold, random appearance than that of plain sliced veneer. Rotary cut natural veneers present the same general characteristics in terms of color as their plain sliced brethren. Again, the amount of sapwood and heartwood will determine the final appearance.
Rotary Cut Red and White Birch
Rotary cut birch presents a more bold, random grain pattern than does plain sliced veneer.
The two examples at left are “A” grade rotary cut red birch (book matched) and the two at right are “B” grade rotary cut red birch (pleasing matched). As in other examples, they do not represent the entire range of color and grain variations that can be expected.
Close-up reveals the grain pattern in
rotary cut red birch veneer.
Rotary cut white birch veneers, like their red counterparts, can come in
“A” grade (the two at left) or “B” grade (like the two examples at right).
Rotary cut white birch veneer patterns
are evident in this example.
Rotary cut birch faces, whether red or white, are available in both “A” grade and “B” grade. The “A” grade faces shown here represent the normal matching method for this grade of rotary cut veneer, be it red or white. The “A” grade doors are book matched in order to obtain a close match in both color and grain at the joints.
Veneers termed “B” grade are pleasing matched and can have veneer cut from more than one log. Within a single face, a “B” grade veneer might have book matched, slip matched or random matched veneer pieces. Color between the veneer pieces within each face will be fairly consistent, but the grain pattern does not have to match at the veneer joints. As a general rule, “A” grade faces cost more than “B” grade faces.
The 1993 revision of the WDMA Industry Standard I.S. 1-A, “Architectural Wood Flush Doors,” changed the identification symbols and grade requirements for hardwood veneers by adopting the standards of the Hardwood Plywood and Veneer Association. Under the revision, “A” grade corresponds to the prior designation of “Premium” grade rotary select white or red birch. The new “B” grade designation corresponds to the prior “Good” grade designation.
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