On a sheet metal layout for bending, where is the sight line measured from?

The sight line in a sheet metal layout for bending is measured one radius from the bend tangent line. This is a critical concept because the sight line acts as a reference point from which the bend is executed.

When creating a bend in sheet metal, the geometry of the bend is determined by the bend radius, which is the radius of the arc formed during the bending process. Measuring one radius from the bend tangent line ensures that the layout accurately reflects the final dimensions of the part after bending occurs. This helps in planning for the material's stretch and ensures that the part will fit correctly once it is bent.

Understanding this measurement technique is essential for any fabrication tasks involving sheet metal, as it directly impacts the accuracy of the final product.