How to Cut a Taper With a Router

Install the router into the router table as per the manufacturers instructions. Install the "tongue" bit into the router. Adjust the bit so that the vertical center of the bit is centered with the thickness of the lumber being routed. Adjust the router table fence so the lumber will feed across the router bit touching the roller bearing.

Feed one side of each of the boards through the router table. Hold the board flush to the router table and the router table fence. Feed the lumber slowly, as this pass will remove a lot of material. Route one edge of every board you are using in the project.

Remove the "tongue" bit from the router and install the"groove" bit. Adjust the bit so that the center of the bit intersects with the center of the lumber's thickness. Adjust the router table fence, if necessary. Pass the un-routed sides of one board through the router table and check the fit of the tongue and groove. Make any necessary adjustments to the bit and fence. Route the un-routed edge of the remaining boards for the project.