Shaping by deforming: woods and metals

Deforming

Deforming is a method of shaping materials by either bending in a straight line or by creating a bowl or dish shape. The key methods for deforming materials in a straight line or in two dimensions are described below:

Bending

Metals can be bent in a vice or in folding bars. Thin metal may be bent whilst cold, while thicker metal may need heating or annealing [annealing: heating a metal to toughen it, so it will not break when bent. Some metals like copper will go red when hot. With those that don't glow like aluminium, put soap on them first, it will be hot enough when the soap goes black. ]. Larger pieces of metal may also need to be heated first.

The material is marked where it is to be bent, and clamped to the line in the vice or folding bars. To prevent damaging the material as you hit it with the mallet, place a piece of wood next to it and hit that instead.

Laminating

Wood is usually bent by laminating. This is done by cutting thin strips of wood, putting glue on the strips and clamping them into a mould [mould: a hollow form into which a softened material is placed. The material hardens and the mould is then removed to produce a product of the desired shape ].

Three-dimensional deforming

Hollowing and press moulding are both ways of three-dimensional deforming it is important to remember that wood will not deform in three dimensions.

Hollowing

Hollowing is a way of deforming thin sheet metal to produce a bowl shape. The metal is first annealed [annealed: (of metals) heated to make it tougher ] then cooled in cold water. Next it is placed on a leather sand bag and shaped using a bossing mallet. Finally it is placed on a hollowed wooden block and shaped it with a blocking hammer.

Press moulding

Press moulding can be used to force sheet metal into 3D shapes. The metal is placed between two moulds which are then squeezed together until the metal takes on the shape of the moulds.