09 Apr A PRIMER ON SAWING LOGS FOR FLOORING
Lumber types are categorized via procedures in which each log is positioned and then cut at the sawmill. The result is a distinctive pattern of the growth rings appearing on the end grain of the board. The most common, PLAIN SAWN (or “flat sawn”) is the least expensive way to transform logs into lumber. The annular rings range from 30 degrees or less to the face of the board.
QUARTER SAWN LUMBER, more costly than plain sawn, has straight grain patterns, where annular growth rings intersect the board’s face at angles of 60 to 90 degrees. Each log is cut into four quarters at a radial angle, resulting in interesting flecking patterns.
Even more expensive, RIFT SAWN is the least common. Here, annual rings range between 30-60 degrees; with 45 degrees the most sought after. Manufactured by milling perpendicular to the growth rings produces a linear grain pattern containing no flecking. This method produces the most waste, increasing cost. Rift sawn lumber is dimensionally stable, and has a unique linear appearance. It is often produced to complement quarter sawn lumber, thus the category, “RIFT & QUARTERED (R&Q).”
R&Q cuts are very dimensionally stable and can withstand seasonal expansion and contraction in wood flooring. Along with stability, these cuts offer higher-ranked hardness ratings than standard cuts. Rift & quarter sawn produces a tight, straight grain running parallel to the board with little to no ray fleck. Quarter sawn displays the straight grain along with ray flecks that run across the grain.
Costs to produce rift & quartered are higher because each log takes a longer time within the sawmill… passing through a saw more times per board foot. R&Q cuts also depend upon state-of-the-art, specialized equipment managed by highly trained employees.
After installation, R&Q results in strong performance characteristics such as being less apt to expand, gap, cup or contract. Top hardwood flooring installers note that R&Q boards expand up and down, as opposed to side to side, (as does a Plain Sawn floor board).
One true American lumber manufacturer has built a strong reputation by consistently delivering the finest R&Q White Oak lumber. For three generations, Graf Brothers has never compromised quality… has always remained 100% loyal to its customer base… and, the Graf Brothers’ name has become a tradition within the hardwood lumber industry. Perhaps that’s in part, why the firm has become the world’s largest manufacturer of rift & quartered lumber.