Designing for sheet metal fabrication involves specific considerations to ensure parts can be manufactured accurately and efficiently. This guide highlights key design rules for common sheet metal processes like cutting, bending, and punching.

Material Thickness

Maintain a uniform material thickness throughout a single part. This simplifies manufacturing and avoids issues with tooling setups.

Bend Radii

Specify internal bend radii that are equal to or greater than the material thickness. Smaller radii can cause material cracking or distortion. Standard tooling often dictates preferred bend radii.

Bend Relief

Incorporate bend relief (e.g., rectangular or tear-drop cutouts) at the ends of bend lines to prevent material tearing and deformation. Relief width should be at least equal to material thickness, and depth should extend slightly beyond the bend radius.

Hole Placement and Size

Holes should be placed at a distance of at least 2-3 times the material thickness from any edge or bend. Hole diameter should generally be no smaller than the material thickness to avoid tool breakage during punching.

Flat Pattern Design

Consider the flat pattern when designing features. Ensure features do not overlap or interfere after bending. Software tools can help generate accurate flat patterns and identify potential issues.

Features Near Bends

Avoid placing features like holes, slots, or embossing too close to bends, as they can deform during the bending process. A general rule is to keep features at least 2.5 times the material thickness plus the bend radius away from the bend.

Material Selection

Choose materials based on strength, corrosion resistance, formability, and cost. Refer to our Sheet Metal Materials page for common options like aluminum, steel, and stainless steel.

By applying these sheet metal design principles, you can optimize your parts for fabrication, leading to better quality, reduced costs, and faster production.