Designing a part for sheet metal fabrication requires a unique set of considerations to ensure it is manufacturable, strong, and cost-effective. Adhering to Design for Manufacturability (DFM) principles is crucial for a successful project.

1. Bend Radius and K-Factor:
The most critical rule is to avoid sharp inside corners. When bending, the material stretches and compresses. Specifying an inside bend radius at least equal to the material thickness prevents cracking. The K-Factor is a ratio used to calculate the flat pattern length by determining the location of the neutral axis within the material during a bend. Accurate K-factor values are essential for a part to bend to the correct dimensions.

2. Hole and Notch Orientation:
To prevent deformation, holes and slots should not be placed too close to a bend line. Maintaining a minimum distance of at least the material thickness plus the bend radius from the bend line is a standard practice.

3. Hemming and Tabs:
Hems—folding the edge of the sheet back onto itself—are used to create safe, blunt edges and increase stiffness. For features that extend from a part, it's important to ensure that tabs are not too narrow relative to the material thickness, as they can be difficult to form.

4. Material Selection:
The choice of material directly impacts the part's function, weight, corrosion resistance, and cost. Common choices include:

• Mild Steel: Low cost and high strength.

• Stainless Steel: Excellent corrosion resistance and hygiene.

• Aluminum: Lightweight, good strength-to-weight ratio, and naturally corrosion-resistant.

By collaborating with fabrication engineers early in the design process, you can optimize your part for efficiency, reduce costs, and avoid common pitfalls.