ENCYCLOPEDIA OF WOOD

FROM LOG TO VENEER

Once its bark is stripped away, a log can be cut into veneer in one of three ways: saw cutting, rotary cutting or flat slicing. Saw cutting, which goes back to the early 19th Century, employs huge circular saws to rip strips of veneer from logs. Although not as efficient as other techniques, saw cutting is still used to produce some crotch veneers from irregularly grained or dense woods such as ebony.

Rotary cutting and flat slicing can produce veneers as thin as Vs to V120 inch and as long as 18 feet. In rotary cutting, a log mounted in a huge lathe rotates against a pressure bar while a razor-sharp knife peels off a continuous sheet of veneer the length of the log. Fir plywood, as well as some decorative veneers such as bird’s-eye maple, are normally rotary cut. Half-round, riff and back cutting are variations that produce veneer from half-logs rather than whole ones.

In flat slicing, a half-log is held onto a frame that swings up and down against a stationary horizontal knife; a slice of veneer is removed with every down - stroke. Flat slicing produces crown-cut veneers. A type of flat slicing known as quarter-cut slicing is used on woods that display a striking figure when quarter - sawn, as in sapele, white oak or lacewood.

VENEER TYPES AND SIZES

SHOP-MADE VENEER

SHOPTIP

Salvaging warped veneer

Crotch and burl veneer sometimes become warped and brit­tle, the result of aging or improper storage. To flatten the sheets, dampen them using a sponge moistened with warm water and stack them on a piece of ply­wood with two or three sheets of newspaper between each slice. Place a heavy weight, such as a concrete block, on top. Let the veneers sit for a day or two. Wrap the sheets in plas­tic and store them under a weight until you need them.