5 Common Mistakes in Designing Parts for Precision Metal Stamping: How to Avoid Them

Introduction to Precision Metal Stamping Mistakes

Design is where every precision metal stamping project begins. A drawing may look perfect on screen, but once it moves into production the realities of tooling, forming, and assembly quickly reveal whether the design was practical. If something is off — tolerances too tight, the wrong material selected, or features arranged poorly — the mistakes can multiply. Suddenly you are dealing with longer lead times, higher costs, and parts that don’t perform as expected.

Precision metal stamping is an incredibly efficient way to manufacture complex parts, but only when the design is aligned with how stamping actually works on the shop floor. At Jennison Corporation, engineers have worked with countless customers to adjust designs before tooling is built, saving weeks of delay and thousands of dollars. This article takes a closer look at five of the most common mistakes in stamping design, why they happen, and how to avoid them.

Mistake One: Overly Tight Tolerances in Precision Metal Stamping

When engineers design parts, there is often a tendency to specify tolerances that are far tighter than necessary. This usually comes from good intentions — no one wants a sloppy fit or a part that fails in assembly. But in precision metal stamping, unnecessary tightness in tolerances creates a ripple of challenges.

Tighter tolerances usually mean more complex tooling. The die needs additional features to hold, form, and cut the material to those exacting standards, which raises the cost of the tool and extends lead time. Press speeds may also need to be slowed to ensure accuracy, cutting into efficiency. Even if production is stable, die life can be shortened, meaning more frequent maintenance and higher long-term costs.

Most importantly, tight tolerances increase the likelihood of part rejection. A batch of stamped parts might technically perform perfectly in the field, but if the inspection process shows even a fraction outside of spec, they will be scrapped. That means wasted material, wasted time, and wasted money.

The better approach is to separate what tolerances are truly critical from those that are not. For instance, a hole diameter that determines alignment with a mating component may require strict limits, but a non-critical bend angle could allow for more variance. At Jennison, engineers work directly with customer design teams to identify which features must stay exact and which can be opened up. This early dialogue often saves significant cost without sacrificing function.

The lesson here is that precision is not free. Every decimal point on a drawing has a price attached, and the key is to make sure the tightest tolerances are reserved for the places where they matter most.

Mistake Two: Wrong Material Selection in Precision Metal Stamping

Material choice is one of the most important factors in stamping, yet it is also one of the most misunderstood. It is easy to select a material based only on its performance in the end product without considering how it will behave under the stresses of stamping. Unfortunately, that often leads to cracks, distortions, or the need for costly secondary treatments.

Take stainless steel as an example. A designer might select a grade that offers high strength, only to discover it is too brittle to form without cracking. Or they may choose a grade that requires surface plating to meet corrosion resistance requirements, adding cost and extra steps to the project.

Jennison encountered this situation when a customer specified a stainless steel that would have been difficult to stamp. The team recommended switching to 304 quarter-hard stainless steel. This grade offered the strength needed but with enough formability to pass through progressive die tooling smoothly. It also eliminated the need for plating, streamlining the process and reducing cost.

The right material balances formability, strength, and finishing needs. That is why material selection should never be made in isolation. An experienced precision metal stamping partner can evaluate both the functional requirements and the stamping process to suggest alternatives that work better. This saves money and prevents delays while still meeting end-use performance.

In short: the wrong material can derail a project, but the right one can make it faster, cheaper, and more reliable.

Mistake Three: Designing Precision Metal Stamping Parts Without Progressive Die Tooling in Mind

Progressive die stamping is one of the most powerful tools in manufacturing. It allows multiple operations — punching, forming, bending, cutting — to take place in a single pass of the strip through the press. But the efficiency of this method depends heavily on the part design.

If a part is designed without thinking about how it will fit into a strip layout, problems arise. Features may be placed in ways that waste material, or geometries may force the strip to move awkwardly through the die. Hole locations, bends, and notches all influence how smoothly the tool can run. Sometimes an inefficient design means two or more dies are required instead of one, multiplying costs.

For example, an extra bend that could have been simplified in design may slow the press dramatically or require a separate operation. A hole too close to an edge may cause tearing unless the layout is adjusted, again adding complexity.

Jennison tackles these issues early by reviewing customer designs and advising how to adapt them for progressive die tooling. By considering the strip layout during design, customers avoid wasted material and benefit from faster, more consistent production runs.

Progressive die tooling is where stamping shines — but only when the design works with the process, not against it.

Mistake Four: Forgetting About Secondary Operations in Precision Metal Stamping

Secondary operations are often overlooked in design, but they can significantly impact cost and lead time. A part that looks complete on screen may still need plating, tapping, heat treating, or deburring once it comes off the press. If these needs are not identified early, they come as unpleasant surprises later.

Some secondary processes are unavoidable. For example, if a part requires threads, tapping is necessary. But many finishing steps can be reduced or eliminated with better design and material selection. As mentioned earlier, choosing the right stainless steel grade eliminated the need for plating in one Jennison project. Similarly, thoughtful edge design can minimize sharp burrs, reducing or removing deburring steps.

Jennison makes secondary operations part of the discussion from the prototyping stage. By mapping the entire lifecycle of a part — from raw strip to final assembly — they help customers understand where additional steps may be needed and how to minimize them. This holistic view of production is one of the most effective ways to cut waste and cost.

When secondary operations are addressed too late, projects get more expensive. When they are addressed upfront, projects run smoother and faster.

Mistake Five: Designing Precision Metal Stamping Parts in Isolation

Perhaps the most common mistake is designing parts without involving the stamping partner early in the process. Engineers often finalize drawings based on their understanding of function, but without input from toolmakers and press operators, those designs may be expensive or impractical to manufacture.

This isolation leads to missed opportunities. A feature might be simplified, saving both tooling complexity and material waste, but only if someone familiar with the stamping process reviews it. In other cases, two parts might be combined into one, reducing assembly costs. Without collaboration, these efficiencies are lost.

Jennison emphasizes collaboration as a standard part of their process. Their engineers review drawings, provide feedback, and advise on manufacturability long before tooling is built. This helps customers avoid costly redesigns, ensures parts can be stamped efficiently, and keeps projects on schedule.

Early collaboration is not just about avoiding problems; it is about unlocking better solutions. Stamping partners see opportunities that may not be obvious from the design side, and bringing that perspective in early makes all the difference.

Thinking Beyond the First Production Run

When designing for precision metal stamping, it is easy to judge success by whether the first production run delivers usable parts. But design decisions also affect what happens six months, a year, or even five years into the future. Tooling wear, material waste, and production speed are all influenced by choices made at the drawing board.

For example, a part that is technically stampable might still shorten die life if certain bends place too much stress on the tooling. Over time, more frequent maintenance and rebuilds add up to real costs. Similarly, if the layout wastes just a little more material than necessary, that waste will accumulate across thousands or millions of parts. Small inefficiencies multiply quickly in high-volume manufacturing.

There is also the question of scalability. A design that works for low volumes may not be efficient when demand grows. Considering production speed, strip layout, and material flow early in the design process helps ensure that the part can scale smoothly without expensive redesigns.

By keeping long-term production in mind — not just the first batch — engineers can protect tooling investments, reduce ongoing waste, and build in flexibility for future demand. In the end, thinking ahead is one of the most cost-effective design strategies in precision metal stamping.

Conclusion

The design stage sets the tone for everything that follows in precision metal stamping. Overly tight tolerances, poor material selection, ignoring progressive die requirements, overlooking secondary operations, and failing to collaborate early are mistakes that drive up costs and risks.

The good news is that each of these pitfalls can be avoided. By working with a partner who values collaboration, understands tooling, and has experience across industries, companies can move from design to production with confidence. Jennison Corporation’s expertise in advising engineers, recommending materials, and planning for manufacturability ensures that projects succeed from the start.

Smart design is not about perfection on paper. It is about creating parts that can be produced efficiently, perform reliably, and deliver value over the long run.

FAQs

What does “design for manufacturability” mean in precision metal stamping?

Design for manufacturability ensures that parts can be produced efficiently and consistently. In stamping, this means choosing appropriate tolerances, materials, and geometries that fit tooling capabilities. It prevents rework, reduces costs, and improves long-term quality.

How early should a stamping partner be involved in the design process?

The earlier the better. Even during early sketches or CAD drafts, a precision metal stamping partner can identify risks and suggest cost-saving alternatives. Waiting until tooling is complete often means expensive rework.

Why is material selection so critical in precision metal stamping?

Different materials respond differently to forming, bending, and cutting. Choosing the wrong material can increase scrap, cause tool wear, or require costly secondary operations. The right grade and temper save time and cost while meeting performance needs.

How does progressive die tooling improve stamping efficiency?

Progressive die tooling performs multiple operations in one pass, producing finished parts quickly and consistently. Designing parts with this process in mind minimizes wasted material and allows for high-speed production.

Do certifications affect the quality of precision metal stamping?

Yes. Certifications like ISO 9001, API SPEC Q1, and ITAR ensure that processes are standardized and quality is tightly controlled. This translates to reliable, consistent parts and compliance with industry-specific requirements.