WoodSkills Issue 02 - Page 49


The opposing grain pattern in each of the boards composing the lamination

Rift-sawn wood has the grain running diagonally or from corner to corner if looking at an end. Rift-sawn wood is used in table or chair legs and is radially cut from a log as opposed to the tangential cuts of plain-sawn boards. Although time consuming to laminate thin boards to form a thick board, there are advantages. A thick laminated board is more stable if the boards are laminated with grain orientation opposite each other. This observation is empirical and gleaned over several years of laminating boards together.

The key is to counter the instability in one board with the other board. The laminated boards then balance each other out with swings in humidity and air temperature. In this photo, this method of lamination can be seen. The distinct growth rings opposing each other in each lamination are visible. After the glue on the pair of laminated boards has cured, the next step is to reduce the thick board down to 1.75 inches. As you recall, one outside face has already been jointed flat. This face is now the reference surface when passing the board through a thickness planer.

It is next necessary to remove 1/4 in. from the overall 2-inch thickness of the board. A few passes through a thickness planer followed by final smoothing with a hand plane accomplishes this. Approximately 1/8 inches is removed with the thickness planer. Once both outside surfaces are parallel and smooth, flip the board for a final pass on the reference surface. The board can is then hand planed to reduce the final thickness to 1.75-inches. You can optionally leave the handplaning step out and use a thickness planer to reduce the thickness of the combined lamination to an accurate 1.75 inches.

Light final passes are recommended as the thick board approaches the 1.75-inch thickness. Exercise care in running the boards through the thickness planer in the correct direction or with the grain to eliminate tearout issues. To avoid mistakes, I typically mark the correct direction along the side of the board using a pencil mark of an arrow. The final passes to bring the board down to 1.75 inches in thickness were performed using a No.7 Jointer plane. This leaves a smooth, hand planed surface. Recall, 1/8 inch was removed from the 2 in. lamination with a planer.