How Lumber is Sawn:
 Plain Sawn
Plain sawing is the most common method of
sawing and consequently most lumber is
plain sawn. Plain sawn lumber is obtained
by making the first cut on a tangent to
the circumference of the log and the
remaining cuts parallel to the first. This
method provides the widest boards and the
least waste; therefore, it is the most
economical. Plain sawn (tangential grain)
is easily recognized by it’s cathedral
(Gothic arch) effect on the face of the
board. The end grain will have
semi-circles and plain sawn lumber tends
to cup more than quartered or rift sawn
lumber.
Quarter Sawn
Quarter sawn lumber is produced by first
quartering the log and then sawing it
perpendicular to the growth rings. All of
the boards sawn thus are of radial grain.
When looking at the end grain, the annual
growth rings will be at 90 degrees to the
face. Quarter sawn lumber is termed
“vertical grain” or “edge grain” in
softwoods. In Mahogany quarter sawn lumber
is termed “ribbon stripe”. This method of
sawing produces relatively narrow boards
and creates more waste. For these reasons
(and the additional handling involved)
quarter sawn lumber is much more expensive
than plain sawn. Quarter sawing evidences
the medullary ray (flake) in the face.
Rift Sawn
Rift sawing is vary similar to quarter
sawing, and has the same advantages and
limitations. This method of sawing
accentuates the vertical grain and
minimizes the flake, common in quarter
sawn oak. The angle of the cut is changed
slightly so that fewer cuts are parallel
to the medullary rays, which are
responsible for the flake effect. Rift
sawn lumber produces an almost straight
grain with practically no flake figure.
Advantages and Disadvantages of These
Sawing Techniques:
Plain or Flat Sawn
1. Less waste but more stable.
2. Easier to kiln dry.
3. More shrinkage in width.
4. Less expensive.
5. Wider widths.
Quartered and Rift Sawn
1. Most waste and therefore most
expensive.
2. Most stable but narrow widths.
3. Shrinks more in thickness than width.
4. More difficult to kiln dry.
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