Bent Wood Shelf

There are several techniques for bending wood, including kerf bending, steam bending, and laminating. Each technique has distinct requirements, advantages, and disadvantages. I chose to use kerf bending for this project, as it really only requires a saw, and seemed very forgiving to quick setup and experimentation.

Kerf bending essentially involves cutting across the wood grain on a workpiece, almost all the way through. A thin top layer is left uncut; with a bit of coaxing, this layer is actually quite flexible, and you can use the cuts to wrap the rest of the wood around a curve.

If that doesn't make sense, I found it pretty hard to explain, but hopefully the photos below can clarify the technique.

After making a series of evenly-spaced cuts across the workpiece, you can wet the wood to loosen up the wood fibers for bending. Next, you apply pressure, with straps or clamps, to bend the wood in the direction you want. After drying, the wood fibers will relax into a new, bent equilibrium, but you can also apply glue to keep the bend totally closed.

I used an online kerf cut calculator to layout my parallel cuts. The spacing determines the final bend radius, and the number of cuts determines the final bend angle. However, for some reason, the final bend of my test piece came out more extreme than the 90-degree angle I designed. So, I reduced the cuts accordingly for my final design.

In addition to the basic design, I added a couple small personal touches. First, I added a small spline to help connect ends together at the bottom of the shelf. Cutting the slots for this spline required some creative jig application on the table saw (see above).

A also decided to hang the shelf using a French cleat at the back of the shelf, which I thought would both hide the connection and serve as a nice focal element for the design.

Sanding and finishing posed some unique challenges. To smooth the interior curves, I tried using sandpaper wrapped around a paint can. This worked out okay, but I later sped things up with a sandpaper-wrapped dowel rod attached to my drill.

To (kind of) match the dark wood accents in our house, I used a wood stain. This being my second time using the stain, I now know that you're supposed to wipe off the excess stain in order to avoid a blotchy mess. I'm pretty thrilled with the results!