As product designers and manufacturers, both of us are always looking for ways to speed up the manufacturing process and make it easier and cheaper. This is where DfM comes in.
Design for Manufacturing, or DFM, is crucial for producing high-quality products and low manufacturing costs. It is a process that enables designers and engineers to optimize a product design for efficient production.
By considering manufacturing methods and constraints during the design phase, DfM can help avoid costly changes and delays in production.
This blog post will explore some of the most critical aspects of DFM, including DFM for different rapid prototyping processes, and provide tips for implementing it into your product development cycle.
What is DFM (Design for Manufacturing)?
Design for Manufacturing, or DFM, is a process by which you can design and create products that are easy to manufacture. It’s an integral part of the overall product design process because it helps you ensure that your product will be cost-effective, efficient to produce, and according to international quality standards.
When designing a product, you must consider how it will be manufactured. You have to consider the product dimensions and shape, the materials used in production, and the labor cost and other costs associated with producing your product.
You can use various DFM processes in the rapid prototyping, including CNC machining, rapid injection molding, vacuum casting, and 3d printing, to see if your great ideas and ambitions can be turned into reality or not.
DFM helps you make sure your design is ready for mass production by considering all of these factors before production.
Why is Design for Manufacturing Important?
Ensure product works as intended
The primary goal of Design for Manufacturing (DFM) is to ensure that your product will look good and functional. If you don’t consider manufacturing issues during the design phase, you may find yourself with a product that doesn’t work in its intended environment (or at all) after assembly.
This happens when designers don’t think about how their product will be manufactured when they’re designing it. For example, suppose there are multiple parts or pieces involved in construction. In that case, these components need to fit together seamlessly during assembly so that everything fits together smoothly without any gaps or overlaps between pieces which could cause problems later on down the road.
Make product cost-effective
Design for Manufacturing (DFM) is vital because it ensures that your product can be made as effectively and efficiently as possible. It also helps you determine how to best use the materials available to you to create a product that’s both cost-effective and sustainable.
Creating a product that can be manufactured efficiently means that it will be easier for your manufacturer to produce it at a reasonable cost, which means you’ll be able to offer your product at an affordable price point. The more affordable the product is, the more people will want it—and the higher demand there is for your product, the more money you’ll make!
Get product sustainable
Designing for manufacturing also helps you ensure that all of your products are made using sustainable materials. This is important because it will help you reduce waste and save money in the long run by cutting down on production costs. If your manufacturer uses less material than necessary, they’ll have less waste, and waste costs money!
Make the manufacturing process more straightforward
With the DFM process, the manufacturing operations won’t be more expensive or complicated than it needs to be. It also means that it can be done quickly and at a low cost if the design changes later.
Increase product quality
DFM helps you avoid problems with quality control. Because you’ve made sure your product can be manufactured in a way that’s easy to check for defects, you’ll have fewer defective products going out into the world.
Consequently, you can save time and money by making fewer mistakes during production, and it will further increase the efficiency of your manufacturing process.
Optimize manufacturing speed
Design for the Manufacturing process can speed up the whole manufacturing process, as it makes a part fit for its manufacturing equipment.
For example, if the part fits appropriately into the machine’s dies, cutting tools can do their jobs more efficiently and produce a finished part in less time.
Let the production process be simple and automated
DFM process can make the part easy to manufacture, increasing a product’s automation potential, as there is less need for human oversight.
A simple design alteration can help in simplifying assembly steps, as a result. For example, you may reduce the number of machines used in the production process and eliminate the need for various setups.
Design For Manufacturing vs. Design For Assembly
Design for Manufacturing and Design for Assembly are two terms that are often confused with one another, but they’re very different things.
Design for Manufacturing (DFM) is designing a product so it can be made cost-effectively. Whereas, Design for Assembly (DFA) is the process of designing a product so it can be easily assembled by the manufacturing companies and/or consumers.
Design for manufacturing focuses on reducing the cost of production by minimizing waste or rework while also maximizing efficiency and throughput.
The goal of DFM is to make sure that each piece fits together correctly and minimizes time spent on quality control while keeping costs low.
On the other hand, Design for Assembly focuses on making sure that assembly is quick and easy to assemble products quickly without errors or confusion. It reduces labor costs by making it easier to assemble components without wasting time or materials.
The goal of DFA is to make assembly easy enough that people who aren’t trained professionals can assemble the product without causing damage or confusion about how everything goes together.
General DFM Principles & Rules
DFM Fundamental Principles
The fundamental principles that should be considered for design for manufacturing (DFM) are as follows:
The right Manufacturing process is essential in product development. When choosing a process, a company should consider several factors – the product’s cost, material, volume, surface finish, post-processing needs, and tolerances – and then select the most appropriate one. It is crucial to finalize the process as soon as possible because other factors highly depend on it.
When designing products, you must ensure that your ideas can be manufactured. You need to know how much your product will cost and how long it will take the manufacturer to produce it. DFM tools can be used in the early design phases to help predict whether a design is practical. Besides, it also helps in reducing the cost and lead times.
During the product development process, you must consider the material you’re using, its grade, and its form. Different materials require different manufacturing processes. You must choose the raw material and shape in the early stages of the development process. This choice depends on your expectations for the product.
The following factors will guide you toward the best material choice for your needs:
- Surface finish (includes anodizing, polishing, plating, coating and etc);
- Opacity (how much light passes through);
- Flammability (how easily a material burns);
- Strength (how much weight something can carry);
- Thermal/electrical resistance (how hot or cold something gets before it changes shape or melts);
- Machinability (how easy it is to cut with machines).
To create a product that functions well, it is crucial to consider the environmental factors of the product’s intended use. When building a product used in extreme temperature conditions, for instance, the specifications will be different from those of a product used in dusty conditions. The difference depends on the intensity and effect these environmental factors have on the product.
You must always keep testing and compliance requirements in mind while carrying out design for manufacturing activities so that they can prevent any hiccups later on. It will never reach the market when a product is manufactured after significant cost reduction but cannot be passed by certifications.
General DFM Rules
Regardless of the type of product, the following general rules will be helpful to you in the DFM process:
Minimize your part count by combining parts into a single component whenever possible. There are benefits to using fewer parts in manufacturing and logistics, including decreased cost and improved efficiency. This will also reduce assembly difficulty, make inspection and testing more effortless, and minimize upfront tooling costs.
Orient the parts correctly as it will facilitate handling. If possible, orient them vertically. Use gravity to your advantage. Design each part to be symmetrical; this way, you won’t have to use sensors or other mechanisms to orient the parts during assembly. If you can’t make a part symmetrical, make it asymmetrical and add external guiding features so that it can be installed correctly.
Designers should try to design multi-functional parts that can serve multiple purposes simultaneously. If the company has multiple products or product lines, it will be more cost-effective to design parts that can be used in more than one product.
Consider the design features that facilitate alignments, such as chamfers, tapers, and moderate radius sizes. It can help you avoid costly assembly errors and damage to your parts or equipment.
To create a more complex design, consider using modular assemblies. This will allow you to change individual components and capabilities without redoing the entire product.
Save money, time, resources, and hassle by using standard components. These standardized parts are more accessible to source, cheaper, and quicker to incorporate into the design and lower the BOM.
It’s important to know what kind of finish you want. Adding a finish might make the part more durable, but it will also make the part cost more money. Therefore, to control or reduce cost, determine which dimensions of the part are genuinely critical and which can be less precise, and give more margin on dimensions that aren’t important.
Design parts to fit into fixtures and machine tools to be fixtures and used on automated assembly lines. It would be very difficult for machine tools and assembly stations to accurately position your part for subsequent operations without these features.
DFM For Different Rapid Prototyping Processes
Different processes offer different trade-offs in terms of design for manufacturability. For example, injection molding, urethane casting, CNC machining, and 3d printing all have different DFM considerations. Let’s read on more.
1. Urethane Casting and Injection Molding
For products that will be cast using the urethane casting process, DFM is particularly important in ensuring that the design can be produced without any defects. Injection molding is another manufacturing process where DFM can be very useful in achieving a high quality final product.
In both urethane casting and injection molding, careful attention to detail is required in the design phase to avoid potential problems later on.
DFM in Urethane Casting and Injection Molding
One primary difference between urethane casting and injection molding is that urethane casting typically has lower molded-in stress than injection molding. This is due to the difference in how the two processes produce parts.
Urethane casting involves pouring the liquid urethane into a mold, where it then cures to form the part.
On the other hand, injection molding involves injecting the molten urethane into a pre-made mold cavity. Because of this, injection molded parts tend to have higher molded-in stress than those produced by casting.
Besides, they also have the following differences that need to be considered in the DFM.
The other difference is the complexity of the model. You can usually do it in urethane casting if it’s a simple, one-piece model. If it’s more complex or has many parts, you’ll need to use an injection molding process instead.
Silicone molds used in urethane casting are less durable than molds used in injection Molding, typically made from steel or aluminum.
The cost of creating a urethane casting mold is significantly lower than the cost of creating an injection mold. Molds for urethane casting can be tooled in days, while it can take longer to get injection molds production-ready.
Injection molding requires stricter wall thickness and undercut tolerances than urethane casting.
Key Considerations DFM for Urethane Casting and Injection Molding
Tolerance is the first thing to watch out for during the manufacturing design process. Tolerance refers to the amount of error that a product can tolerate, and it’s often expressed in mils (thousandths of an inch).
Injection-molded parts must be manufactured within extremely tight tolerances to fit together seamlessly. Urethane casting can be more forgiving, but it’s still essential to maintain high precision throughout manufacturing.
So you need to choose the proper manufacturing process. If you’re creating a product with tight tolerances and significant features, you can go for Injection molding. Else urethane casting is more economical.
The undercut is one of the significant considerations during the design for manufacturing of the part.
A component has a hole or cavity inside it that prevents you from inserting any tool (like an awl or screwdriver) into that area without damaging its surface or edges.
Undercuts make it difficult for manufacturers to assemble products without damaging them during the assembly process–which is why they’re so important!
Besides, the impact of undercut varies according to the manufacturing process. In the injection molding process, the impact is more as its mold is usually made from steel or aluminum, which is not flexible.
The impact is considerably lower in Urethane casting due to flexible silicone molds that can be bent and stretched while tooling to release the part.
Another concern is wall thickness—the distance from one side of an object to another (think of a cube). Wall thickness can affect how well your part functions and its durability, so it’s essential to keep tabs on how thick each piece will be before you start producing prototypes.
The thickness of the part must be consistent from one end to another so that the material doesn’t weaken or warp as it cools down during casting or cooling down after injection molding.
2. CNC Machining
In terms of the manufacturing process, CNC machining is a more complex processing method. DFM helps a lot to simplify the process and ensure that all parts are machined correctly.
Why is DFM important in CNC Machining?
In CNC machining, DFM is the process of measuring and monitoring the dimensional accuracy of the part being produced. It is an integral part of controlling variation in the manufacturing process.
Following are the key factors why DFM matters in CNC machining:
Design for manufacturability helps ensure that a manufacturer can make your parts or that your product’s design is manufacturable. This can be the case even if the design has some unique characteristics that have not been seen before in CNC machining, as long as these characteristics do not compromise the product’s performance or other important factors. So, with DFM, design drawings, and CNC prototyping, the designers ensure that the design can be turned into reality or not!
DFM brings together all elements of a product’s design, including parts layouts, heat transfer analysis, and parts design. This makes it easier to identify defects and avoid them during production.
If you don’t have Design for Manufacturing, your production will be delayed while people try to figure out whether or not the products are good. But if you do have DFM, you’ll have fewer mistakes and save production time and money.
DFM Tips for CNC Machined Parts
When selecting a material for CNC parts, consider the strength and hardness of the material and its compatibility with the machining process.
It’s essential to make sure that the parts of your CNC machine are accessible. If the machine can’t reach its parts, production efficiency will decrease, and manufacturing costs will rise.
All CNC drills have a circular shape, making it difficult to achieve sharp internal corners. Therefore, it is better to avoid sharp inside corners whenever possible.
To machine a hole in metal, use a drill bit or an end mill tool.
When using a CNC machine to make thin-walled products, you need to be careful. The product walls will be weaker and more likely to warp or soften than usual. Consequently, reducing the product reliability and quality. Therefore, try keeping the wall thickness above 0.02″.
Tight tolerances are essential for some parts, but using tight tolerances can increase costs when they’re not needed.
When deep pockets are an integral part of your product, the best approach is to either reduce their depth or increase their width.
Design your parts for functionality rather than appearance to lower cost and minimize the lead time for CNC machining services. Consider simplifying or eliminating any features that aren’t critical to the part’s function.
To save costs and time on machining, it’s best to design chamfers rather than fillets as exterior features on your CNC machined parts.
When designing components for an assembly, we recommend leaving 0.1″ (2.54 mm) clearances between parts to ensure a proper fit.
3. 3D Printing
DFM is especially important when it comes to 3D printing, as the technology is widely used, and there are many details that should attend.
What is DFAM (Design for Additive Manufacturing)?
DFAM is a design philosophy that focuses on creating products that are easy to 3D print. This means using materials that are compatible with the additive manufacturing process, designing parts that can be printed without supports or rafts, and making sure that the design of your product doesn’t require any complicated support material or post-processing after it’s printed.
Designing for additive manufacturing can help you save time and money by making it possible to print larger quantities of your product faster and with lower material costs and usage.
How to Design for 3D Printing Manufacturing?
If you want your 3D printed product to be successful, you must take the time to design for 3D printing manufacturing. This means making sure that your design is adaptable and flexible enough to be manufactured with relative ease.
There are opportunities to reduce lead times and manufacturing costs both in your product and your production line. By streamlining your processes and making improvements where possible, you can minimize waste and save time and money.
Here are some tips on how to design for 3D printing manufacturing:
Please make sure all parts are removable or interchangeable to be easily replaced by the manufacturer as necessary.
Include as few moving parts as possible—this will ensure that the product will last longer in the field, which will help boost sales!
Pay attention to the types of materials used in manufacturing; if possible, choose durable or reusable materials so they can easily be recycled or reused when necessary.
Ensure your design is optimized for the most efficient use of materials. For example, if you have a product with many small parts, it could be cheaper to print them in two or three larger parts instead of printing each part individually using more material.
Try 3D printing the product in different orientations to see which one gives you the strongest result with the least amount of support material.
Ensure that the wall’s thickness of the 3D printed part is in the right proportion to your printer’s bead thickness. This will optimize build times, reduce material cost and usage, and increase product quality and durability.
Ensure your part height is a whole multiple of your printer’s Z thickness. It will reduce manufacturing costs and time.
Get DFM For Your Project At WayKen
DFM will have all the stakeholders involved in product development come together and solve problems directly related to the product design, its processes, and the manufacturing process. This ensures a smooth transition of the product from design to assembly up to the mass production level.
Design for Manufacturing is a process that helps you get the best results. At WayKen, we are expert in CNC machining, vacuum casting, and 3d printing. For each project, we conduct a DFM review to ensure that your prototypes and parts are produced in the best and most cost effective way. Contact us today!