What is a Wood Spline?
A wood spline is nothing more than a long, thin strip of wood that acts as a splice between two planks. It is the same thickness as the tongue side of a wood plank. Splines allow the flooring to be worked in opposite directions effectively cutting the installation time in half. Larger room areas over 30 ft. benefit from added center expansion and this is achieved by starting the installation at the center of the room using splines, following an establish chalkline (figl). Splines should always be glued and nailed into place (fig2) .
The easiest way to make a hardwood spline is to simply rip a thin strip from a board. But now imagine putting a lot of stress on a miter joint assembled with a thin, long-grain spline. Hie spline would likely split along the grain and the joint would come apart.
The best way to make a hardwood spline is shown in the drawings at right. This technique for cutting crossgrain splines from a short scrap is just a little more involved but the result has a couple of big advantages.
Since the grain of the spline is running across the joint, there's no chance of the spline splitting and the joint tailing. A second benefit is appearance. As you can see in the inset photo on the previous page, the exposed end of the crossgrain spline matches the grain of the mitered pieces.