How to Bending Wood

Bending wood is not the daunting task that seems at first sight. Depending on the degree of the curve, and if the curve is complex, there are a couple ways to bend wood.

First, you need a way to bend the wood around and clamp to maintain the thedesired. Most bent wood will have a degree of "elastic", so you have to create a form with an allowance for this. And unfortunately, there is no set formula for determining the degree of elastic recovery to a particular species of wood will produce. Springback is also influenced by the folding method used. That is, the steamed wood will spring,
or "straighten" more than wood that is laminated and glued. Another variable is the type of adhesive used in lamination.

As a general rule, the greater the curve, more wood spring back, making the allocation of a matter of trial and error at best.

As rolling thin strips is the easiest method, we begin with this process. The final thickness of the project will directly affect the size of the strips to be used, but overall, the best strip of use is about ¼ "thick. Bends may have to be made with 1 / 8" or thin strips, depending on the species of wood. Sounds like a lot of experimentation, but I'm afraid that is a necessary evil.

The form required for laminating can be as simple as a piece of pipe or as complex as a multi-station die. I like to keep things as simple as possible.

When laminating thin strips, can minimize effort and spring again soaking the strips before bending, and clamping the mold without sticking. Once dry, remove the mold, spread the glue and clamp back into the mold. Line pan with waxed paper to prevent sticking to the mold lamination.

When dipstick me, I do it in an open container, and depending on the wood and the size of the strips, I soak for 15 minutes at night. Also mix in half cup of fabric softener per gallon of water. I think it softens wood nearly as well as the fabric.

If the project is small, and free time in the queue is not a factor, I'll use poly-vinyl-acetate, or aliphatic resin glue. If I need more time to work, I'll use epoxy or resorcinol. I'm staying
far from epoxy resins, fast setting, however, because they rarely become hardened to the extent that the slow sets do. If you are using light colored wood, resorcinol dries to a reddish color that may be objectionable in a finished project.

When bending thin woods such as guitar parts, wood is commonly soaked as above, but bent over a hot bending template, either electric or hot with a propane torch. Fragile forests are supported on the outside of the curve with a thin band of stainless steel to help prevent cracking.

Green woods can be bent much the same way, or by heating the wood over hot coals or heat gun.

For projects where lamination is objectionable, or when the wood is going to bend compound curves, a steam box is the answer. One can be quite economically from PVC pipe, but needs to be supported to maintain the pipe deformation.

The pipe ends must be closed with a screw cap on at least one end, to allow access to the interior. Wrap the other end of the pipe with a DWV cut shirt, and attach a radiator hose to the side entrance and a new gas can be large enough to store enough water to function at work. The water can be heated with a hot plate or a propane burner.

Drill through the pipe slightly below center in two or three locations and insert dowels for the wood to rest. Steam can circulate freely around the wood, even for penetration. A hole about ½ "in diameter should be drilled in the lid off the steam
input to allow circulation. When you build the support framework for the steam box, field box
toward the steam inlet to allow condensation to return to the water source.

Rule of thumb is that the wood should be steamed fifteen minutes per inch of thickness, but again, some experiments will be necessary.

The wood needs to be placed in the way as quickly as possible, as the wood cools, it is harder to bend. Make sure your timber is at least two feet longer than the finished piece because it is almost impossible to bend a 3 / 4 "piece of wood that is less than a foot long, so the last foot will have to be cut
off after the wood is dry.

Clamp the wood securely, and leave it to cool completely. If you are working with several pieces, place in steam table, an approximately the interval required to place the piece in the manner and the clamp, and out of the box in the same order.