Plasticization of wooden material increases by heating starting from a temperature of 70°C up to the optimum temperatures of between 145-150°C. As regards to humidity, the most convenient percentages are between 14 to 16%, but they may reach up to 25%.

From the physical point of view, maximum plasticity is reached due to compression, minimum in the strain zone (elongation).
During treatment the neutral line, that is the area where the two forces are balanced, tends to move towards the external area of the arc thus increasing the plastic section.
In order to facilitate this movement further, devices are used (shaped forms) which prevent elongation during bending.

Furthermore, if the hot curved wood is allowed to cool and dry in the form, the curve stabilizes and the wood re-acquires its original strength.

The production of solid curved wood has therefore three distinct phases:

• plasticization due to the action of the heat;
• bending;
• stabilizing of the bending by drying of the wood at temperatures above 65°C.

In order to achieve satisfactory results wood without knots and defects such as fibre deviations and internal stress must be used.