# Defining-the-Bend-Allowance

By catia programmer

This section explains the calculations related to folding/unfolding operations.

When a bend is unfolded, the sheet metal deformation is represented by the

bend allowance V defined by the formula:

When a bend is unfolded, the sheet metal deformation is represented by the

bend allowance V defined by the formula:

**L = A + B + V**where:

L is the total unfolded length

A and B the dimensioning lengths as defined on the figures below: