How to Kerf Wood to Prevent Swelling

Prevent swelling by kerfing the wood with a table saw.

A kerf is a small, shallow cut that doesn't penetrate through the wood's surface. Kerfs can be made side-by-side on wood to relieve tension and make the wood pliable. You can use kerfs to prevent swelling of wood on the underside of chairs or furniture that is exposed to moisture, the backside of siding, flooring -- or even counter tops in high moisture environments -- to prevent swelling and buckling. You can use an ordinary table saw to kerf wood.

Things You'll Need

• Table saw
• Tape measure

Instructions

1. Raise the blade on the table saw to 1/4 inch from the tip of the highest tooth, to the point where the blade emerges from the saw.

2. Set the fence at 3/4 inch from the blade. Place the wood behind the blade, against the fence. Turn on the saw.

3. Push the wood across the blade. Pull it straight back until you can see the blade again.

4. Set the fence 1/4 inch farther to the right. For example; you started with 3/4 inch, set the fence at 1 inch. Push the wood across the blade and pull it back.

5. Reset the fence 1/4 inch farther to the right and continue cutting kerfs, moving the fence 1/4 inch to the left with each pass until you have cut kerfs completely across the wood.

   The bottom of the wood should look like a comb when you are finished.

Tips & Warnings

• The measurements here are for examples using approximately 3/4 inch wood. You can cut kerfs any depth you like. For example; if your wood is 1 inch thick, cut your kerfs 1/2 inch deep. If your swelling problem is not considered severe, cut your kerfs 1 inch apart.

• Always wear safety glasses when working with wood.