Metal stamping design is not only about part geometry, but also about manufacturability, tooling cost, and production efficiency. A well-designed stamping part can significantly reduce material waste, tooling investment, and production defects.

This guide covers short-run stamping, material selection, and key sheet metal design for manufacturability (DFM) rules.

When to Use Short-Run Stamping Methods

Short run stamping is typically suitable when production quantities are below 20,000 parts or when tooling cost exceeds part cost.

• Prototype and pilot production

• Spare parts manufacturing

• Low-volume industrial products

• Projects with tight delivery timelines

Compared to progressive dies, short-run tooling can reduce tooling cost by up to 6–8 times and significantly shorten lead time.

However, unit cost, material waste, and labor costs are generally higher.

Material Selection for Metal Stamping

Ferrous Metals

Cold-rolled steel is the most widely used metal stamping material. Low carbon steels (0.05%–0.20%) offer good formability and low cost.

For deep drawing applications, aluminum-killed steel provides superior ductility.

Nonferrous Metals

Common nonferrous materials include:

• Aluminum alloys (1100, 3003, 5052)

• Copper and brass (excellent formability)

• Nickel alloys and magnesium alloys

These materials are selected based on strength, corrosion resistance, and forming requirements.

Nonmetallic Materials

Materials such as plastics, rubber, and fiberboard can also be processed using stamping die methods, mainly for blanking and piercing.

Stock Utilization in Stamping Design

Efficient material utilization is a key factor in reducing cost.

• Design shapes that allow tight nesting

• Reuse scrap material for smaller parts

• Coordinate design with strip layout

For example, L-shaped parts utilize material more efficiently than T-shaped parts.

Hole Design Rules for Stamping Parts

Stamping hole design must follow certain guidelines:

• Minimum hole diameter ≥ material thickness

• Hole spacing ≥ 2× thickness (3× preferred)

For close hole positioning, stress relief features such as auxiliary windows may be required.

For high precision alignment, secondary operations or pilot positioning may be used.

Corner Radius and Narrow Section Design

Sharp corners should be avoided in metal stamping design:

• Minimum radius ≥ 0.5× thickness

• Avoid stress concentration

Narrow sections should be at least 1.5× material thickness to prevent deformation and tool breakage.

Screw Threads and Extruded Holes

Because sheet metal is thin, screw thread design requires special consideration.

• Thread diameter ≤ 2× thickness (steel)

• Use extruded holes to increase thread length

Extrusion height typically reaches 1–1.5× material thickness.

Burr Control and Edge Design

Stamping burr control is important for safety and functionality.

• Place burr side away from functional surfaces

• Avoid unnecessary deburring operations

• Design bends to hide burr edges

Proper burr direction can reduce secondary processing cost.

Formed Parts Design Guidelines

• Prefer standard bending angles (90°)

• Maintain width ≥ 3× thickness to prevent distortion

• Use standard tooling where possible

These rules reduce tooling complexity and cost.

Drawn Parts Design Guidelines

Deep drawing requires careful design:

• Avoid sharp bottom corners (radius ≥ 4× thickness)

• Do not specify both inner and outer diameter

• Prefer cylindrical shapes over complex geometries

For short-run production, drawn parts are often replaced by fabricated assemblies to reduce cost.

Engineering Insight

In real production, many stamping issues such as cracking, distortion, or poor alignment are caused by improper design rather than material defects.

Optimizing geometry, material selection, and process planning is critical for achieving efficient and stable production.

Conclusion

Metal stamping design plays a key role in production efficiency and product quality. By applying proper DFM rules, manufacturers can reduce tooling cost, improve material utilization, and minimize defects.

For more about stamping fundamentals, see metal stamping process.

At Changdong Tool & Die, we specialize in metal stamping die design and manufacturing. With extensive experience in both short-run and mass production tooling, we help customers optimize part design, reduce cost, and achieve reliable production.