Different methods of veneer manufacture
Different slicing methods are used to produce different visual effects. Logs of a given species, cut by different methods will produce a variety of appearances.
In rotary cutting, the log is mounted centrally in the lathe and turned against a knife, as if unwinding a roll of paper. A multi-patterned grain marking is produced with this method. Rotary cut veneer can be sufficiently wide to provide full sheet (one piece) faces.
Flat cut, flat sliced, crown cut or plain sliced are synonymous terms used in different countries. The half log (flitch) is mounted with the heart side away from the knife against the flitch table of the slicer. The slicing is done parallel to a line through the centre of the log. This produces a distinctive 'cathedral', or heart figure. The ratio of quartered to crown faces produced by this method naturally runs about 60-40% in favour of crown.
The width of the veneer sheet depends on the size and species of the log. The oaks can produce widths in excess of 410mm, however requirements for specific sized logs should be pre-arranged between buyer and seller. Plain slicing produces the largest width veneer of the slicing methods as a log is cut into two flitches before slicing. The other slicing methods use logs which have been cut into several flitches prior to slicing.
Quarter slicing involves first cutting the log into four pieces. Then the manufacturer places the quarter log (flitch) 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 species, varied in others. The width of veneer produced through quarter slicing is less than plain slicing, with an average less than 200mm - depending on log size. The 'flake' appearance in oak is produced by the quarter slicing method.
Veneer is sliced on an arc roughly parallel to the centre of the log to achieve a flat cut appearance. The 'cathedral' pattern can have more rounded tops than the pattern produced by flat slicing.
Rift-cut veneer is produced from the various species of oaks. The logs are cut into four pieces.
Rift-cut veneer has a straight grained look, which is obtained by periodically changing the cutting angle to stay about 15 degrees off the quartered position to avoid the 'flake' figure. The width of veneer produced through rift-cutting is less than plain slicing, with an average less than 200mm - depending on log size.
A board of flat sawn lumber is passed flat over a stationary knife. As it passes, a sheet of veneer is sliced from the bottom of the board. The width of the veneer and figure produced with this method depends on the width and figure of the sawn lumber and is typically variegated.