How to Make Hardwood Flooring Using a Router

Set the fence of your router so it’s flush with the grooving bit. Place a straightedge against the side of the fence and move the fence over the bit until the bit touches the straightedge while the straightedge is still in place. Adjust the fence of your router so it’s straight with the bit position. This will ensure you maintain an even depth throughout the groove you run the piece of hardwood along the bit.

Place a piece of scrap wood the same thickness as your hardwood planks onto the router against the fence. Adjust a combination square to the 1/4-inch mark. Use it with a pencil to place two parallel lines 1/4 inch from the base of the wood and 1/2 inch from the base of the wood onto both ends of the plank. Adjust the height of the bit to set it between the lines on the wood.

Set the fence on the router to run the board through the bit. Start the router and push the board along the bit to cut a groove. Turn off the router, flip the board over and press the board against the router to see if the router fits within the groove. If it does, the router is centered correctly and there’s no need for adjustment; if it doesn’t, adjust the router up or down to center the cut in the board as needed and test it on the other side of the board. Continue to adjust and test the router until the groove is centered.

Cut grooves into all of the flooring planks needed using the correctly set router.

Remove the grooving bit and replace with the tongue bit. Set the height of the two blades on the tongue bit so the top edge bottom blade is even with the bottom of the groove in the test piece and so the bottom edge of the top blade is even with the top of the groove. Cut a test piece in a piece of scrap and test the fit of the tongue on the scrap to the groove on the final test piece. If the surface is even, the heights of the router bit blades are set correctly. If the surfaces are uneven, adjust the heights of the blade as needed, testing the blade on scrap until you have a properly positioned tongue.

Run the boards you cut the grooves into through the router to make the tongues on the other sides.