What method is used to prepare plywood for bending?

Soaking plywood in hot water is an effective method for preparing it for bending due to the way heat interacts with the adhesive bonds within the plywood layers. Hot water causes the wood fibers to soften, making them more pliable and allowing for easier manipulation and bending without breaking. When the plywood is immersed in hot water, the temperature raises the moisture content and reduces the stiffness of the wood, which is critical for achieving the desired curvature while maintaining the integrity of the material.

Exposing plywood to steam is another common method and can also facilitate bending, but soaking in hot water is often preferred for its simplicity and effectiveness in soaking the plywood thoroughly, especially for larger pieces. Other methods mentioned, such as soaking in cold water or vinegar, do not provide the same level of pliability needed for successful bending. Cold water would not soften the wood effectively, and vinegar would not have the desired effect on wood fibers in terms of flexibility for bending applications.