7 sheet metal design mistakes that increase your manufacturing costs

In industrial subcontracting, the difference between a “good” part and a truly cost-effective one often comes down to design. A CAD model may look perfect on screen, but if the part hasn’t been designed with manufacturing in mind, it can lead to extra costs, longer lead times, and assembly issues. That’s where Design for Manufacturing (DFM) becomes a strategic lever.

At Graphie, we believe a good part shouldn’t just be well designed it should also be easy to manufacture, stable in production, and optimized for cost. That’s why we review your projects through a manufacturing lens from the start, identifying anything that could slow down industrialization or unnecessarily increase costs.

Seven mistakes to avoid in sheet metal fabrication

1. Underestimating bend radius

A poorly defined bend radius may seem minor in CAD, but on the shop floor it can complicate bending and weaken the part. When the inside radius is too small, the material is overstressed and the risk of defects increases.

In practice, it’s better to define radii that align with material thickness and real production capabilities. The result: smoother fabrication, fewer adjustments, and fewer surprises.

2. Placing holes too close to bends

A hole positioned too close to a bend line can deform during forming and lose accuracy. This quickly becomes an issue during assembly.

By respecting proper distances at the design stage, you avoid rework, manual adjustments, and added costs at the end of the process.

3. Specifying unnecessarily tight tolerances

Tighter tolerances don’t always make a part better. In many cases, they simply make manufacturing slower, more expensive, and harder to control.

The best approach is to focus precision where it truly matters: functional areas, assembly interfaces, and critical features.

4. Overlooking corner reliefs

When bends are close to edges or intersect, the material needs space to form properly. Without proper relief, you risk deformation, internal stress, and a less clean result.

Well-designed corner reliefs improve bend quality, consistency, and reduce the need for rework.

5. Adding welds when bending would suffice

Every welding operation adds time, labor, and often additional finishing. In many cases, a well-designed bent part can effectively replace a more complex welded assembly.

Reducing secondary operations simplifies production, improves consistency, and increases efficiency.

6. Ignoring metal grain direction

Rolled metal is not perfectly uniform. Depending on the orientation, certain bending directions perform better than others.

By considering grain direction early during nesting, you increase the likelihood of producing more reliable and production-friendly parts.

7. Designing flanges that are too short

A flange that’s too short can make bending difficult or even incompatible with standard tooling. This kind of detail can block production or require costly special solutions.

By validating geometry early with your manufacturer, you secure the process and avoid last-minute adjustments.

Why Graphie

At Graphie, we don’t just manufacture parts we help you design them to be easier to produce, more robust, and more competitive. Our team reviews your files as soon as they are submitted to identify optimization opportunities, eliminate unnecessary operations, and improve overall project efficiency.

Whether it’s nesting, geometry, bending, or assembly operations, our goal remains the same: helping you turn a good idea into a well-manufactured part without unnecessary compromise.

Sources : Thomas https://cdn.thomasnet.com/ccp/30335290/189641.pdf