Bending wood transforms solid, straight wood into graceful curves. It’s often an adjunct to another project, such as building furniture, baskets, musical instruments, toys, or crafts. Wood can also be softened by creating multiple cuts on the back of the wood. This method is called kerf-cutting.

What types of wood can you bend? All wood can be steam-bent usefully to some extent, and the good woods are ‘Temperate Hardwoods’ (Ash, Oak, Chestnut, Walnut, Cherry, Beech, Sycamore, Elm) and also Yew is fantastic. The best woods are also ‘ring porous’ (Ash, Elm, Oak, Chestnut).

Generally, heat and moisture can offer up to 10x the bending of room temperature timber. As a rule of thumb, steam bending in a proper autoclave with the normal thickness (20 > 54mm as a guide) should see 1 hour of steaming per 25mm of timber thickness.

You can steam bend soft woods (including pine, cedar and spruce) but if you were attempting this, again it would be best to use air dried wood – as kiln dried wood tends break or snap more easily during the bending process.

The Best Wood for Bending Most of the wood suitable for bending comes from deciduous trees like birch, hornbeam, maple, alder, oak, ash, and poplar. We use coniferous species like pine, cedar, and larch less often. For the manufacture of bent glued blanks, birch veneer is best suited.

Southern pine wood can be successfully steam-bent if the bending jig incorporates a flexible metal bending strap together with a mechanism to apply a uniform end compression load during the bending operation.

They have to soak the wood in water to bend it and get it into a certain shape. To efficiently make the wood bendable, it’s recommended that you soak the wood in relatively hot water for one to three hours. Many other factors can change this, but one to three hours will work for most wood types.

Steaming or soaking the wood in boiling water to soften it. 2. Saw-kerfing or grooving the back of the wood so it will bend easily without danger of splitting or cracking. Keep pouring boiling water over the top every few minutes to keep it hot.

Build a box and add a steam kettle: you’re ready to bend wood. Building a steam box for bending wood only requires exterior-grade plywood, waterproof glue and an electric tea kettle. I bought my kettle from Lee Valley (see Source, below). It came with an aluminum pipe to direct steam into the box.

Add screen door hooks to keep the doors shut as you steam away. Steam passes from the kettle to the box through a pipe inserted into the kettle’s spout. The kettle must be refilled now and then during the steaming process; two guide blocks help position the pipe when you re-insert it in the hole.

Note: Steam-bent parts partially spring back after cooling and drying. Build your bending and drying forms to slightly over-bend the part to compensate for springback. Make bending forms from particleboard or plywood laminated to a thickness equal to the width of the bending blank.

In bending thick pieces of solid wood, however, softening with steam or hot water or plasticizing with chemicals is essential. When a piece of wood is bent, it is stretched, or in tension, along the outer (convex) side of the bend and compressed along the inner (concave) side.