Which of the following is NOT a common method of modifying structural members?

Chamfering is not typically considered a common method for modifying structural members in the context of construction or plumbing. Instead, it refers specifically to the process of beveling the edges of a material, usually to facilitate assembly or improve aesthetics, rather than altering the underlying structural integrity or configuration of members.

On the other hand, reinforcing involves adding additional support or materials to enhance the strength or load-bearing capability of a structural member. Cutting is a fundamental method used to adjust the dimensions or fit of structural components, allowing for corrections or adaptations in the construction process. Curving refers to the alteration of structural members to introduce a bend, often necessary in applications that require non-linear forms, contributing to both design flexibility and functional requirements.

Each of these methods—reinforcing, cutting, and curving—directly impacts the strength, function, or fit of structural members, while chamfering does not fit this category in the same way, thereby establishing it as the correct answer to the question.