DFM – What Is Design for Manufacturing and How Does It Save Costs?

Product design is a very complex process because of the difficulty of translating ideas into real-world feasibility. Sophisticated and advanced models can be created based on an idea, but this does not necessarily mean that turning the model into a product will be possible, efficient, or economically worthwhile.

This is where the DFM process, short for Design for Manufacturing, comes into the picture. Its purpose is to ensure in advance that the design is adapted to manufacturing capabilities. This guide explains how it works and how it saves money and prevents problems.

What Is DFM?

In Hebrew, DFM means design for manufacturing, and in practice it is a stage in which the product design is examined from an engineering perspective during the early stages of development. Instead of designing a product and only afterward trying to understand how to manufacture it, the DFM process ensures that every design decision takes the manufacturing method, materials, costs, and production rate into account.

This approach is relevant to every manufacturing method: machining, plastic injection molding, laser cutting, metal forming, and more. The guiding principle is to design the product so that its manufacture is as simple, efficient, and cost-effective as possible.

Why Is It Important to Consider Manufacturing During the Design Stage?

Most product costs are determined during the design stage, even before any machine begins operating. Industry studies show that approximately 70% of a product’s manufacturing cost is derived from decisions made during design. Changes made at a later stage, when the mold is already ready or after the production line has been defined, are several times more expensive than changes made during the design stage.

A common example: An engineer designs a mechanical part with deep, narrow grooves that require a dedicated tool and a lengthy process. A small adjustment to the geometry during the design stage can allow machining with a standard tool, save machine time, and reduce the cost per unit by tens of percent.

What Are the Advantages of DFM?

The DFM process produces measurable advantages in several areas:

• Savings in manufacturing costs – Adapting the design to the manufacturing method reduces material costs, machine time, and the number of required operations. Studies indicate average savings of 20% to 40% in manufacturing costs
• Shorter development times – Identifying manufacturing problems at an early stage prevents expensive correction rounds and accelerates the transition from prototype to serial production
• Improved product quality – A design that takes the manufacturing process into account reduces variation between parts, decreases the product rejection rate, and ensures consistency throughout the production run
• Reduced complexity – DFM makes it possible to reduce the number of parts in the product and simplify product assembly
• Prevention of production line problems – An adapted design reduces stoppages, malfunctions, and delays during serial production

How Is the DFM Process Carried Out?

The DFM process is carried out through cooperation between design engineers and manufacturing personnel. In many cases, an external party with in-depth knowledge of manufacturing capabilities and limitations is used.

The main stages of DFM include:

• Analysis of the existing design – Examination of drawings and CAD models, identification of potential manufacturing problems, and evaluation of compatibility with the planned manufacturing method
• Selection of a manufacturing method – Matching the product requirements, including quantities, tolerances, and material, with the most appropriate manufacturing method
• Geometry optimization – Adjustments to the part design that simplify the manufacturing stage, including changing radii, reducing deep grooves, adapting tolerances, and more
• Material selection – Selection of raw material according to the manufacturing process, mechanical requirements, and budget constraints
• Verification and testing – Production of a prototype, testing compliance with the requirements, and correction of findings before the start of serial production

Adapting the Design to the Manufacturing Method

Every manufacturing method presents different constraints and requirements, and proper design must take them into account in advance. Here are two examples:

In machining processes, or CNC, the structure of the part, the access of the tools to the different areas, the depth of cavities, and the required level of accuracy must be taken into account. For example, deep and narrow pockets require the use of a long and thin tool that tends to vibrate, making accuracy more difficult and therefore extending machining time. A design that takes the depth-to-width ratio into account saves machine time and improves surface quality. In addition, unnecessarily tight tolerances increase the cost without providing practical benefit. The rule is to define a strict tolerance only where it is truly required.

In plastic injection molding processes, consideration must be given, among other things, to wall thickness, mold structure, the way the part is removed, and the behavior of the raw material during the manufacturing process. Uneven wall thickness causes uneven shrinkage and creates distortions in the finished product. During design, uniform wall thickness should be maintained, draft angles that allow smooth removal from the mold should be added, and emphasis should be placed on the injection point and material flow. Careful design helps manufacture a product without distortions or sink marks and with minimal waste.

Common Mistakes in Product Design for Manufacturing

There are several mistakes that recur in product development projects and should be recognized in order to prevent them:

• Overly strict tolerances – Defining high accuracy for all dimensions of the part, even when it is functionally unnecessary, increases the manufacturing cost and extends manufacturing time
• Ignoring tooling constraints – The geometry should be designed according to the size of the cutting tool, the access angle, and the working height in order to minimize the use of special tools or additional processes
• Choosing unsuitable materials – It is important to choose a raw material that is mechanically suitable and is not too difficult to machine or too expensive in relation to the requirement
• Designing without draft angles – In parts intended for plastic injection molding, a design without sufficient draft angles causes damage to the part or mold during removal from the mold
• Too many parts – If parts can be combined and assembly can be simplified, there is no reason to design a product consisting of a large number of separate parts

These mistakes can be prevented with an organized DFM process in cooperation with a party that has in-depth knowledge of the manufacturing world.

Adamati: Professional Support in Design and the Transition to Manufacturing

Adamati supports engineering projects from the stage at which the product is still on the screen through full serial production. We have extensive experience in mechanical and electromechanical components, and we offer a wide variety of manufacturing methods under one framework: precise CNC machining of aluminum, steel, titanium, and copper, plastic injection molding using advanced technologies including overmolding and multi-cavity molds, laser cutting, metal forming, vacuum casting, and rapid prototyping using 3D printing.

Our team assists in examining the design against manufacturing capabilities, selecting the appropriate manufacturing method, and making the adjustments required to manufacture efficiently, at high quality, and at an optimal cost. We work with a wide variety of industries, including high-tech, electronics, medical, defense, and semiconductors. Contact us to examine your project and adapt a manufacturing solution according to the product structure, quantities, and quality requirements.

Questions and Answers About DFM

When Should the DFM Process Begin?

The earlier the design-for-manufacturing process begins, the better. The optimal timing is during the detailed design stage, before molds are manufactured or raw materials are ordered. Changes at this stage are much cheaper and faster than changes during the manufacturing stage.

Is DFM Also Relevant for Small Quantities?

Yes. Even in small-quantity manufacturing processes, an adapted design can save machine time, reduce the need for dedicated tools, and improve product quality. The larger the production run, the more the savings accumulate and become more significant.

What Is the Difference Between DFM and DFA?

DFM stands for Design for Manufacturing, design that focuses on manufacturing each part separately. In contrast, DFA, short for Design for Assembly, focuses on simplifying the assembly of the parts into a complete unit. In practice, the two processes complement each other and are usually carried out together.

How Much Can Be Saved Through DFM?

The level of savings achieved through DFM varies according to the complexity of the product and the manufacturing method. Studies indicate average savings of 20% to 40% in manufacturing costs, and in some cases even more. The savings result from using less material, shortening processing times, reducing the number of parts, and preventing correction rounds.

Does DFM Require a Significant Change to the Product Design?

Not necessarily. In many cases, these are small adjustments that do not change the function or appearance of the product, such as adding radii, changing wall thickness, or loosening tolerances in non-critical areas. The result is a product that looks and operates the same but is manufactured more efficiently and at a lower cost.