Designing for additive manufacturing can be a challenge, but it's also a fun and rewarding process. This guide will discuss tips and tricks to help you create designs perfect for 3D printing. We'll also look at some benefits of additive manufacturing and how it changes the operations of a business.

What Is Additive Manufacturing?

A house being 3D printed with a 3D printer and an illustration of a helmet near it

Additive manufacturing is a technology that builds objects by successively adding material layer-upon-layer until the object is created. It is more commonly known as 3D printing. AM technology has existed since the 1980s.

In the early days, it was limited in terms of usable materials and the type of objects we could create due to the size and shape limitations of the printing process. Nowadays, there are multiple 3D printing technologies, machines, and materials available, which means that there are very few objects that cannot be manufactured using this technology.

Benefits of Additive Manufacturing Over Traditional Manufacturing Processes

Additive manufacturing brings a slew of benefits. They include:

  • Reduced lead time between design and the final product.
  • Increased design freedom.
  • Increased accuracy.
  • Reduced wastage of materials.
  • Flexibility in production—for example, small-batch or one-off production runs can be economically viable.

These factors make additive manufacturing ideal for small businesses and niche markets where classical manufacturing processes would not be viable. In addition, as more products are designed with additive manufacturing in mind from the outset, we will likely see a reduction in the overall cost of goods and a further increase in design freedom.

How to Design for Additive Manufacturing

Before you start designing for additive manufacturing, you need to consider some vital things. Let's take a look.

1. Ensure That the 3D Model Is Waterproof

Water being poured to three designs that have been 3D printed to check if they are water tight
Image credit: XYZAidan/YouTube

One of the benefits of design for additive manufacturing is that it allows you to create complex geometries that would be impossible to achieve with traditional manufacturing methods. However, this also means more water opportunities to get into the design and cause problems. To ensure that your 3D model is waterproof, you'll need to take a few extra steps during the design process.

  • Ensure that all the channels and voids in the design are sealed. If there are any areas where water could potentially enter, add drains or other features to help keep the water out.
  • If you find any leaks in your design, you can fix them by adding or moving vertices until the mesh is completely sealed.
  • Another way to prevent leaks is to use a higher-resolution mesh. This will create a smoother surface that is less likely to have gaps or holes. Balance the resolution of the mesh with the complexity of the model. If the mesh is too dense, it will be challenging to edit and slow your computer.
  • Finally, consider using materials naturally resistant to water, such as certain types of plastics or metals. These precautions can help ensure that your 3D model can withstand water exposure.

2. Check on Shrinkage and Warping

A demonstration of a warped 3d print
Image Credit: CNC Kitchen/YouTube

Amid all the talk of design for additive manufacturing, it's important not to lose sight of the fact that post-processing still matters. One area that still needs attention is shrinkage and warping (see how to avoid warping in 3D prints).

Traditional manufacturing methods are controlled by design features such as chamfers and draft angles. But with additive manufacturing, the build orientation can significantly affect shrinkage and warping. As a result, checking for these defects before starting the build process is essential. Doing so can avoid surprises and ensure that your parts meet the design specifications.

3. Consider the Overhangs

When designing for additive manufacturing, you should keep the overhangs in mind. Overhangs occur when a part of the design hangs over space without support. This can be problematic because the material is deposited layer by layer during the printing process. Nothing underneath supports the material, which can collapse and ruin the print.

Add supports to the design to provide stability during printing. Alternatively, the angle of the overhang can be adjusted so that it is less likely to collapse. As long as you don't overlook this area when designing for additive manufacturing, you can be sure to produce high-quality prints.

4. Consider the Strength of the Model

When designing for additive manufacturing, it is crucial to consider the model's strength. Unlike traditional manufacturing methods, AM builds parts layer by layer from a pool of liquid or powder. As a result, these parts can be weaker in certain directions and more susceptible to breakage.

To ensure that your AM part is strong enough to withstand the stresses of use, it is crucial to consider its orientation during the design process. For example, if you are designing a part that will experience high-stress levels in one particular direction, consider orienting the layers of the part so that they run perpendicular to that direction.

As a result, DfAM engineers must carefully consider the strength of the materials they are using and the design of the part itself to create final functional products.

5. Check the Resolution

An demonstrating the resolution settings of a 3D model in Cura slicer

When designing components for additive manufacturing, it is essential to consider the model's resolution. The resolution is a minor feature that can be accurately printed, and it is limited by the size of the deposition nozzle and the layer thickness. For example, a model with a resolution of 0.1mm would not be able to print features more minor than 0.1mm.

Higher-resolution models are more expensive to produce, but they can be essential for printing fine details or complex geometric shapes. When choosing a resolution for your model, it is crucial to balance cost and accuracy.

6. Consider the Escape Holes

When creating an object with multiple parts that need to be attached, designers must consider that there will be voids or spaces between the pieces. These voids can cause problems during printing, as they trap air and prevent the part from bonding correctly to the build plate. One way to address this issue is to include escape holes in the design.

Escape holes are small openings that allow air and excess material to escape during the printing process, thereby preventing trapped air from causing problems during the printing process. So, including escape holes in the design is crucial for anyone interested in designing for additive manufacturing.

7. Avoid Undercuts and Sharp Corners

A 3d object with sharp corners being designed in a 3D modeling software

Design is critical in 3D printing. One common mistake is to design objects with undercuts or sharp corners. These features may look fine on a computer screen but can cause problems during printing. The reason is that 3D printers build objects one layer at a time.

If an object has an undercut, the printer may be unable to lay down the material properly, resulting in a weak or deformed part. Sharp corners can also cause problems, as they are prone to warping or breaking during printing. Therefore, it's better to prevent undercuts and sharp corners by opting for designs you can easily print without issues.

Test Your Design Before Sending It to the Printer

Now that you know how to design for additive manufacturing, it's important to test your design before sending it to your 3D printer. This will allow you to assess how the design works in the additive manufacturing process and identify potential issues. It's also an excellent way to get an idea of the costs involved in 3D printing your product.

Once you've tested your design and are happy with the results, you can send it to the printer. With these valuable tips in mind, you can ensure that your product will be printed correctly and to your specifications.