You can set the bend deduction to a negative value to correctly represent the corresponding bend allowance.Occurs somewhere between the midpoint of the material (K-factor=0.50) and a point closer to the inside of the bend (K-factor=0.25). The inside of the bend is under compression, the outside is under tension, and the neutral axis Relates to the depth of the neutral axis a line within the sheet where the length does not change Of the metal thickness and depends on factors such as the material and type of bending operation. for a Bend Allowance or Bend Deduction, it will override the values obtained from the bend table or computed using K-factor Parameter of bends in a sheet metal part used to calculate the bend radius. This panel is initially displayed on the lower left side of the screen, but can be moved. If you enter values in the Properties panel Area of the user interface that displays editable details about the selected object(s).If some bends in the part use Vee Die and other bends in the part do Not, the assigned bend table file must specify a table with no Vee Die Width entry.If a bend table is assigned to a part, the Bend Allowance is obtained from the table and the assigned bend table file must specify tables for all possible combinations of part thickness and Vee Die width.

If a bend table is not assigned to a part, the Bend Allowance is calculated from the default K-factor found in the Sheet Metal options.This means that the OSSB is the same as the outside radius of the bend. See the image below.įor bend angles greater than, or equal to, 90-degrees, the OSSB is measured from the beginning of the bend to a plane tangent to the outside bend face. When you pull a sketch into 3D with the Pull tool, lines become edges., which is the intersection of the planar faces. Depending on the bend angle, SpaceClaim uses two different definitions of OSSB as explained below.įor bend angles less than 90-degrees, OSSB is measured from the beginning of the bend to the Outside Mold Line A straight line, arc, or spline drawn in Sketch mode or on a layout plane.

The neutral line is the radius where the material transitions from compressive stress (inside) to tensile stress (outside)

BA is the Bend Allowance that equals the arc length of the bend along the neutral line.

The tables are based on the Bend Deduction (BD) formula, which calculates the flat line length to produce a specific bend angle. You are here: Working with sheet metal > Unfolding sheet metal components > Using a bend deduction tableīend deduction tables are used to calculate flat pattern layouts.

Tubing bend allowance chart