Wood Selection

Types of Wood

Wood types from left to right: walnut, cherry, maple, poplar, red oak, basswood, mahogany, Spanish cedar, and ebony.

Natural Wood

Trees are made of hollow vessels that transport water and food up and down the branches and trunk to the roots. These vessels give cut wood the visible lines we call grain or figure. Grain can add contrast and texture to a project, but it also affects the project’s structural integrity. Wood is strong across the grain, but it breaks easily along, or with, the grain lines. Position delicate protruding design elements so they connect to the rest of the project with the grain running the length of the element.

Wood splits easily with the grain, which is visible as lines in the wood, but remains strong across the grain. Choose the grain direction that is the strongest for your project design.

Natural wood expands and contracts depending on the relative humidity of the air. Different types of wood react at different rates to humidity changes. If you join two types of wood, those differences can cause some joints to fail. For example, if you use solid wood as a box bottom that is fully enclosed by the sides, the bottom can expand and literally break the box apart.

Wood expands and contracts depending on the relative humidity. This expansion can break glue joints. Allow an expansion area between components when constructing boxes.

For the most part, woodworkers choose wood for a project based on how easy it is to work with, the price, or the color. Most common hardwoods, including walnut, cherry, maple, and poplar, are suitable for scroll saw projects. These varieties of wood are easy to cut and sand, and are readily available. Oak is also easily available and will work for some projects, but the strong grain pattern may not appeal in every design.

Another common wood to consider is basswood. It is easy to cut and shape, and its light color allows you to stain or dye it nearly any color. Basswood is also relatively inexpensive.

Once you step outside the commonly available hardwoods, you can find a wide variety of colors and grain patterns. Many of these exotic hardwoods come from tropical climates. Exotic hardwoods vary greatly; mahogany and Spanish cedar are easy to work and moderately expensive, while black ebony is hard, dense, and expensive.

In addition to occasionally being difficult to work, exotic hardwoods sometimes contain natural oils that act as irritants and can cause anything from sinus infections to skin rashes. If you plan to use an exotic hardwood project such as a basket or bowl to hold food, seal it well with shellac, lacquer, varnish, or a food-safe finish.

The natural oils in hardwoods can also make them difficult to glue or finish. Test finishes on scrap wood, and wipe the areas where you plan to apply glue with a strong solvent, like acetone, before applying the glue.

Manufactured Wood

Manufactured wood has its own pros and cons. Plywood is made of thin layers of wood glued together. In each layer, the grain runs perpendicular to the layer below it. This makes plywood strong and durable, but instead of solid end grain, plywood has obvious layers.

Because the grain direction alternates in each layer, plywood does not expand and contract due to humidity. This makes plywood a good choice for a project, such as a box, that is fully enclosed within the sides. The stable plywood will not push the side joints apart.

MDF, which is made of ground-up wood fibers glued together under high pressure, has no visible grain. Instead, it’s a uniform brown color. However, MDF is not as durable as regular wood or plywood. Also, MDF can absorb moisture, so seal it thoroughly if there is a chance the project will get wet.

If you plan to paint a project, plywood and MDF are both good choices. Both are easy to paint, and the paint will disguise the end layers. If you apply a natural finish to plywood, the visible layers of wood can give your bowl, basket, or box a unique look.

Plywood (above left) is made from layers of wood glued together. MDF (above right) is made from ground-up wood fibers glued together.

Joining Wood

Many projects require you to glue sides or layers of wood together. Or, you may choose to glue (or laminate) different types of wood together to add color and contrast to a project.

To make a strong glue joint, attach two pieces of wood along the flat planes with the grain running in the same direction, called face to face. You can also edge glue two pieces together to make a wider blank, but make sure the grain runs along the edges to be joined and in the same direction on both pieces. Any joint involving end grain is weak, including unsupported miter joints. Plan your projects to avoid gluing end grain or reinforce the joints with dowels, screws, or brads.

Use strong joints to create a durable project. 

Common wood glue, such as Titebond or Elmer’s, will work for most projects. Polyurethane glues, such as Gorilla Glue, will also work well if you remove the foam those glues create before you finish the project. Cyanoacrylate (CA) glue, such as Super Glue, is useful to hold pieces together while another glue sets, but CA glue isn’t as durable as wood glue. Tacky-type craft glue grabs faster than wood glue, and we often use it for purely decorative projects, but the bond isn’t as strong as wood glue. For projects that will be frequently handled, such as bowls, baskets, and boxes, use a durable wood glue.

You can use almost any wood to make your woodworking projects. For best results, plan ahead and be aware of the unique properties of wood and how they will affect your project.

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