Bending Wood – Different Techniques Used

How often have you gazed in wonder at the beautiful intricate shapes of wooden architecture, marvelling at the sheer creativity of the workman? Such extraordinary shapes and designs can be made only with the aid of bended pieces of wood. So how can this bending be done? There are various methods that can be adopted some of which have been since time immemorial, for e.g. right from the middle ages.

Steam bending is one such method practiced by people down the ages. A look at the processes involved in this method:

First of all you’ll need a few articles like a box in which the wood to be bent has to be placed, some water in a container, a hose or a pipe to let in the steam and some screws and clamps, not to forget a source to supply heat. The process begins by clamping down the wooden piece into a mold and placing it in the box. One end of the hose has to be inserted in the box while the other end lies in the water container. Once you heat the water the hose will transfer the steam into the steam box. One major advantage with this method is that the wood retains the long grain pattern with no apparent glue marks. Wastage of material is minimal here. This is most suitable for straight grain lumber. This method can be quite time consuming though, with a 1/4th inch lumber piece taking around 20 min to 2 or more hours for a piece of roughly 2 inches.

Kerf Bending: Here a Kerf or cut is made into the inside edge of the piece with the aid of a chop saw. Then these saw cuts are filled and the bending is done so that these cuts close. While making the cuts, be careful not to cut more than 2/3rds in thickness for anything more than that will cause the wood to break while being bent. This method was widely used in the construction of Victorian houses which sported rounded corners both on the internal as well as external sides.

Microwave Bending: One of the more modern approaches to wood bending is the microwave method. It can be likened to steam bending but is faster. This method is applied mainly to soften the wood and for molding it. It can also be used for partial heating of the material. In this process, the wood is placed in a wet paper towel and microwaved. The time is fixed according to the thickness of the wood. Best thing would be to give it a 20 second heating to test the pliability of the piece and then experiment further.

Laminated Wood Bending: In this method, thin layers of wood are chosen because they bend easier. The thin strips are placed in a mold and laminated together with the help of glue and clamped down firmly. Thin strips can be bought or can be sawed out of thicker pieces. Ideal thickness of each piece would be about 1/ 8″. Usually the finished piece will be longer than needed in which case you’ll have to trim the edges

Some of the lesser used methods are chemical and alkali softening, compression bending, cold bending etc.