Since its introduction into the world in the 1980s, additive manufacturing has been making a massive impact on the planet. Every single year additive technologies advance more and more. When done correctly, additive manufacturing speeds up the production process, reduces waste, and saves companies a ton of money. One important function, in particular, is additive manufacturing's role in product validation.
The EV market has brought about a surge in demand for the latest and greatest vehicles. It has also magnified the massive automotive supply chain disruption, especially with recent chip shortages. What it has also brought to the world is the need for innovation with additive manufacturing. Manufacturers are now being asked to prototype and validate new parts in much shorter timeframes. This post will take you through how companies use additive manufacturing to support this need. We will also take you through some of the fundamentals of this technology and the available techniques commonly used today.
What is Additive Manufacturing?
Additive manufacturing is the process of joining materials to make objects from 3D model data, usually layer upon layer. Each added layer will then serve as a base for any additional layer. It's very common to see additive manufacturing and 3D printing as interchangeable terms, but it's worth noting that there are processes that are uniquely part of the additive manufacturing category.
Value Adds of Additive Manufacturing
There are plenty of reasons why additive manufacturing has been growing exponentially over the years, but the primary value adds are:
- Part Development Speed - With additive manufacturing, you can create parts in hours vs. days/months.
- Design Modification Speed - You can modify the design for better performance on a tighter timeline.
- Design Concepts - Multiple concepts can be printed and validated at once.
- Concept Validation - Allows for faster concept validation which translates to a quicker time to market.
- Cost - Cheap compared to traditional manufacturing methods for low volumes of parts, mainly due to the cost of traditional tooling.
Additive Manufacturing Techniques
Over the years, there have been several additive manufacturing methods developed. These techniques range from the basic versions of 3D printing you might perform at home to more advanced methods.
In this section, we’ll take you through four of the more common forms of additive manufacturing, along with the pros and cons of each.
Fused Deposition Modeling (FDM)
FDM is one of the most popular 3D printing technologies today due to its lower cost and ease of use. The way it works is plastic filament is extruded from a nozzle layer-by-layer onto a build platform. While the material is still warm, the layers fuse to produce a 3D object.
Pros - Wide range of production-grade materials, low cost, large build volume
Cons - Low-quality resolution and surface finish, weaker part strength between layers, build support required
Best Used For - Large, simple parts
Ultraviolet (UV) laser selectively cures liquid thermoset resin layer-by-layer to produce a 3D object.
Pros – High accuracy, high resolution, durable parts, quality surface finish
Cons – Limited selection of “Like” materials (not production grade), expensive, small build volumes, and build support required.
Best Used For- Small detailed parts
Selective Laser Sintering (SLS)
A laser sinters powdered material layer-by-layer to produce a solid plastic object
Pros – High accuracy, high throughput, medium grade surface finish, excellent mechanical properties, supports not needed
Cons – Limited materials, expensive
Best Used For - Detailed parts, higher volume of parts
Small droplets of liquid resin are layered onto a build surface and UV-cured layer-by-layer
Pros – High accuracy, high resolution, multiple materials can be printed at once
Cons – Limited materials, build support required, expensive
Best Used For - Functional prototypes, detailed prints
Product Validation Methods Using Additive Manufacturing
With additive manufacturing, there are a TON of different ways you can use the process to validate parts. So, what we are going to do here is just take you through a few methods of how we use it to give you a better idea of how it can work.
This is the most obvious one, but being able to physically create your product in minutes/hours is huge when validating a part. 3D printing is the number one way that product prototypes are made today, and for a good reason.
To do this, you’ll want to have a solid understanding of additive manufacturing methods and the material you plan to use. When it comes to 3D printing, you’ll likely not get that ultimate "final product" look and performance that you can achieve with full production methods, like injection molding. Still, with the newer technologies, you can get extremely close.
Custom Testing Fixtures
While 3D printing the part you want to validate is great, it’s not the only way to take advantage of additive manufacturing. Echo commonly utilizes the technology by developing custom testing fixtures to ensure that prototyped or production parts can meet specific testing requirements.
One example of how we’ve used it here is for insertion/extraction force testing related to electric vehicle panel plugs and automotive coolant line protection caps. With additive manufacturing, we have been able to design and develop custom fixtures for each part to be used on our tensile test machine.
3D Printed Molds
3D printing rubber is much more complex compared to what you may see with plastics. Materials like silicone can not be heated and extruded, nor can they be cured with UV light. Instead, they require highly specialized 3D printers that you’re unlikely to find. Even then, part design and geometry are limited due to several factors.
Luckily, other options still allow us to develop production-grade rubber parts for design validation. One method in particular that we have at Echo is using additive manufacturing to build custom molds to produce production-grade silicone and EPDM components.
Additive Prototypes vs. Hard Tool Prototypes
Subtractive manufacturing is the opposite of additive manufacturing as it typically comes in the form of creating a mold out of either steel or aluminum plates where you machine out the cavities where the prototype part will be molded. Compared to additive manufacturing, this method will typically create pieces with more of a finished appearance, with little to no post-processing required (part/material dependent).
You can create prototypes using either method, but there are several critical differences between t, so we broke it down into a few. To simplify it, we broke down the primary deciding factors (Cost, Time, & Risk) when choosing between them.
Additive – The price per piece will be higher, but the biggest perk comes from no hard tooling needed.
Hard tool – Expensive tooling cost and design change will require tooling modification or potentially a new tool. Domestic injection molding tools can be very costly, making it difficult to justify one or more prototypes.
Additive – Once you have your design, the 3D model can be loaded and printed in hours or days.
Hard tool – It’ll likely take approximately 5-10 weeks to get parts in hand due to the time spent designing and developing tooling.
Additive – The main issue with additive prototypes typically comes from parts not being production-grade or having production quality issues. Another issue is developing a design can only be printed, but would not be able to be massed produced using traditional methods.
Hard tool – The two primary risks of going with a hard tool prototype is the longer lead time to validate designs and the level of difficulty that can come from design modification needs.
One other element that's worth mentioning is the differences in materials. Each method gives you a variety of materials that you can choose from, but the properties of those materials are going to differ based on what method you use.
With all the technological advances today, the most significant limitation in additive manufacturing may simply be a lack of thinking outside the box. With additive, you aren’t limited to only printing a prototype part. There are countless other ways to take advantage of the advancing manufacturing method.
If you’re looking to prototype your next part, you’ll want to ensure you partner with the proper manufacturer or be willing to invest time and capital into 3D printing technology. Our inside support team and design engineers will be ready to help get your project going. Contact us today if you have any questions or want to take the next steps toward bringing your part to life.
About Echo Engineering
Echo Engineering specializes in domestic and international molding processes, engineering design, prototyping, and validation. We consider customers' design needs, tooling options, time restraints, and the need for a working solution that meets or exceeds requirements.
Our history of additive manufacturing dates back to 2012 when we first invested in 3D printing. Echo has since expanded our capabilities by investing in new machinery, which includes equipment that creates prototype compression molding molds for silicone and EPDM parts.
Echo's additive manufacturing expertise has helped bring a variety of parts to life for some of the world's most significant electric vehicles, heavy machinery, and powersport manufacturers, among many others.