Walnut has a long history in woodworking, especially furniture making, where its use dates back to England before the settlement of the American colonies. Much of the quality furniture manufactured in the early history of America was made of black walnut, an American variety of this English favorite. While oak enjoyed several decades as the number one wood, partially due to its cost, walnut is now making a resurgence in popularity.
Part of walnut’s popularity stems from it being the only dark colored domestic hardwood, although American Willow leans towards the dark side. This makes it so that of all the dark colored hardwoods available for woodworkers to use, walnut is the least expensive. Depending on where it is purchased, it ranges from $7.99 to $12.99 per board foot, with the lower prices mostly coming from bulk suppliers. But for those who make a lot of furniture, buying 100 board feet of lumber to keep on-hand is not a serious problem.
Walnut is a fine-grained wood, largely straight-grained, but with some waves and curls. Depending on the boards purchased, it can combine a dark chocolate colored heartwood, with a caramel colored sapwood. Finished projects finish to an extremely smooth surface with a high luster. It is also highly durable, being more scratch and dent resistant to even red oak, which is known for being an extremely durable wood. Walnut is one of the few woods which will lighten up over time. Some furniture-makers overcome this tendency of walnut by applying walnut stain to their finished projects, before varnishing. The use of stain can also help to darken the sapwood, giving the entire project a more even appearance.
The black or American walnut tree grows throughout the eastern part of the United States. However, it only accounts for about one percent of total wood production, driving the price up. Trees mature at 150 years, reaching a height of as much as 150 feet, with a trunk diameter of 8 feet. The slow growth of the tree also serves to drive the price of walnut hardwood up.
Because of the cost, walnut is often used in veneer form, either veneering directly onto other, lower-cost hardwoods or in the form of hardwood plywood. Even in a veneer form, the durability of walnut remains, which makes it one of the more ideal woods for making furniture, as is proven out by the vast number of pieces of antique walnut furniture which has not only survived, but is still in excellent condition. Building a table, out of walnut hardwood plywood, with hardwood edges, for example, balances the opposing forces of making quality furniture, while keeping the price down. Veneering furniture has long been considered an acceptable means of extending available wood resources and keeping furniture prices down. Walnut veneer is available in sheets up to 12’ long.
As plywood, walnut is available with either sliced or rotary cut face veneer, giving the woodworker a greater selection in the finished appearance of their project. Plain-sliced veneer will have a more obvious grain pattern, as the process of cutting the veneer crosses the rings of the log, while rotary cutting goes around the rings. However, as trees are not perfectly symmetrical, rotary cutting can produce some dramatic cathedral grain patterns.
Walnut plywood is typically available in ¼”, ½” and ¾” thicknesses, with either veneer core or combination veneer & MDF core. In the case of the former, birch cores are common, virtually eliminating the problems of voids and knots. In the case of the latter, a thin layer of MDF is applied as the outer veneer, just under the face and back veneers. This provides an extremely smooth surface for the veneer to be applied to, helping to create plywood, and therefore projects, with a superior finish.
Visually, walnut and black walnut are virtually identical, especially after finish. As any wood has variance in coloration anyway, the two can be used together in a project, without it causing any problems. While one might think that walnut plywood would not be as durable, due to the walnut face veneer being so thin, it is remarkably durable, as the veneer still resists scratching and denting.
While walnut is a tight-grained wood, considerably different from the open grain of oak, it can still benefit from the use of a paste wood filler to fill the pores in the wood. Properly tinted, the paste wood filler will bring out the grain in the wood in an even more pronounced way. At the same time, the wood filler helps provide a smoother surface, giving the overall project a glass-like finish.
Varnish is the preferred finish for furniture made out of walnut, with a matte finish varnish being the most popular. For an ideal finish, hand-rubbed varnish is hard to beat. But this is not the only finish that can be used on projects made of walnut plywood. Tung Oil is another popular finish for walnut, especially for non-furniture applications.