Finger joint boards are engineered lumber created by joining smaller pieces of wood together to form longer, wider, or thicker boards. These smaller pieces are precisely cut with interlocking "finger-like" projections, which then interlock and are glued together to form a solid unit. This process allows manufacturers to create larger and more consistent boards from smaller, often less expensive pieces of wood.
How Finger Joint Boards are Made
The manufacturing process involves:
- Cutting: Smaller pieces of wood are cut at an angle to create the interlocking finger profiles.
- Joining: The cut pieces are precisely aligned and fitted together.
- Gluing: A strong adhesive is applied to secure the joints.
- Pressing: The joined pieces are pressed together under pressure to ensure a strong, even bond.
- Finishing: The resulting board is often planed smooth and may be primed or treated for painting or staining.
Advantages of Finger Joint Boards
- Cost-effectiveness: Often less expensive than solid wood boards of comparable size.
- Consistent size and quality: Reduces variations in width, thickness, and appearance compared to solid wood.
- Availability: Offers wider dimensions and lengths that are difficult to achieve with solid wood.
- Suitable for various applications: Often used in trim, shelving, and other interior applications where strength and dimensional stability are important (though strength can vary depending on joint quality and application).
Disadvantages of Finger Joint Boards
- Strength limitations: While generally strong enough for many interior applications, finger joint boards may be weaker than solid wood boards, especially under stress applied directly to the joints. The strength is highly dependent on the quality of the glue joint and how the stress is applied. Some sources indicate that they can be stronger than solid wood under compression but weaker under lateral stress.
- Appearance: The finger joints are visible, which may be undesirable in some applications. However, many find the joints unobtrusive, especially after priming and painting.
Examples of Finger Joint Board Uses
- Interior trim: Baseboards, crown molding, casings
- Shelving: For light to medium-duty shelving applications.
- Furniture components: Used in certain furniture parts where appearance isn't paramount.
The strength and suitability of finger-jointed boards depend heavily on the quality of the manufacturing process and the intended application. While they may not be suitable for all projects requiring maximum strength, they offer a cost-effective and readily available alternative for many interior woodworking applications.
