Manufacturing Medical Plastic Parts: 3D Printing and Injection Molding
COVID-19 created uncertainty in product development timelines producing medical plastic parts. Future demand for your products or services is more in doubt now than ever before. And, you are likely re-thinking plans for 2021.

All of this impacts the supply chain. Which means organizations must be more agile and constantly reassess each step in the product development process.

Still, organizations are likely to return to a normal planning modus where they can look into the future to commit to product volumes and launch timelines.

In this blog we discuss:

Manufacturing during a crisis
Product development and prototype processes
When to use 3D printing
When to use plastic injection molding
How both processes can complement each other
Manufacturing medical components during a crisis
Product demand uncertainty
The crisis of 2020 revealed the fragility of the global supply chain. As a result, many industries were left scrambling to find distribution channels.

However, the medical industry faced different issues. For one, confirming product quantities. And second, finding capacity to fulfill product demand.

For example, consider a medical device company that pre-pandemic secured contracts to supply equipment to 1,000 hospitals in North America. Post-pandemic those hospitals’ budgets are in disarray. Which means the medical company is likely unsure of the product volume needed. Or, if any will be needed at all.

U.S. Food and Drug Administration (FDA) Testing
Producing medical components can be trickier than for other industries. On one hand, you still have to achieve fit, form, and function. On the other, you consider more stringent criteria for some healthcare applications and FDA testing.

Now consider all of this in the context of a pandemic like COVID-19. For one, it could mean a delay in FDA availability. Further, your in-house testing may have been halted or repurposed.

So, how can medical companies prepare for future uncertainties? First, by becoming more agile when using 3D printing and injection molding. And second, by following every step in the product development process.

Product Development And Prototype Tooling
Product Development
The product development process can be viewed as a continuum where each phase builds upon the last. Thereby enabling us to gather information necessary to bring a high-quality injection-molded product to market. This is why following each step is critical to bringing medical components to market on time and on budget.

Prototype Tooling: Impact for medical plastic parts 
The cost, time, and energy for making changes to your part increases as you progress through the product development process.

In fact, this increase is about 10X that of the previous step. Which can result in costly product launch delays. And, if you produce medical plastic parts, this can impact patients’ lives as well as revenue.

Benefits of investing time in prototype tooling
Investing time in prototype tooling can mitigate risk when producing medical plastic parts.

At TISS, we use our proprietary Process Engine software to help eliminate part defects. This allows us to continually learn and improve upon not only parts in active production, but the manufacturing process as a whole.

The learning aspect is critical because we want to get the execution exactly right for each step in the process. In doing so, we can provide more informed suggestion to our clients about what needs to be done.

3D Printing and Injection Molding for Medical Plastic Parts: Same Team Different Roles
 
3D printing and injection molding are manufacturing processes used for producing plastic parts. They each have unique strengths and limitations. And, they also work to complement each other.

Unfortunately, mistakes are made when producing medical plastic parts because of common misconceptions about these processes.

3D printing: common mistakes and limitations
Common mistakes
One common mistake made is the failure to acknowledge that end-use criteria are radically different from those guiding a form/fit/function-type prototype. The three major differences between prototype and end-use product are:

Material properties
Accuracy
Surface finish
“For example, adding the requirement of initial function for testing purposes reduces the number of processes and materials available via the additive manufacturing process,” said Brianna Gillett, Account Executive at TISS.

“Then, when you expand an end-use product’s capabilities to fit a specific application, it further reduces the number of processes and materials available to keep additive manufacturing viable. Finally, the hurdle is production rate, which naturally is related to the unit cost of the outcome.”

Limitations of 3D printing for medical plastic parts
Because it is so easy to use, reliable, and affordable, some organizations invest in 3D printing technologies for early-stage prototypes. 

However, the further you progress through the development process, the more complicated projects become and the more difficult it is to achieve the desired outcomes.

“For this and several other reasons, some may think they can skip the prototyping step of the product development cycle,” Gillett said. “But the vast majority of products have at least some changes in design or functionality. And this is when to consider injection molding as a next step.”

Injection molding for medical plastic parts
Simply put, the injection molding process creates plastic parts by injecting molten plastic into a mold. As the material cools, it begins to take the shape of the final product. For complete details about the process, please visit page, injection molding process.

When to consider the injection molding process:
Projects at scale
Higher volume production runs (anything more than a few hundred parts)
Final part design (after prototyping)
Parts of any size or complexity
Objects that will mate together or move against one another 
As discussed earlier, the product development process includes a series of steps. And following each step can help to stay on track for budget and time-to-market. One of the most critical steps is prototyping. 

Prototype injection molding
For example, consider the way a polymer fills steel or aluminum tooling. The physical act may not go the way it was simulated, following exactly the process as interpreted by an ideal situation in a lab.

So if variations are outside the range of acceptable parameters, you will not be able to tune the process to achieve the desired outcome. Which could result in defects like warp and other aesthetic blemishes.

These are the easy fixes that can be caught in intermediate prototyping steps. 

3D Printing and Injection Molding for Medical Plastic Parts: Same Team, Different Roles
Using these 2 processes together can help to bring your products to market faster.

In the case of medical device companies, especially during the pandemic, this can literally mean the difference between life and death.

To meet product launch objectives and ensure everything is on target, an ideal approach is to conduct initial low-cost 3D printing following simulation, then progress to pre-production and rapid injection molding tools. Learning everything you can about the processes and product can mitigate risk when moving to production.

3D Printing and Injection Molding: Personal Protective Equipment (PPE)
A great and very timely example of this is how 3D printing and injection molding are being applied to produce PPE. During the COVID-19 crisis, PPE includes testing swabs, ventilator components, and other items.

These complementary processes have been able to address medical equipment needs quickly in areas where the materials were appropriate. However, the need for extremely high volumes of these items (as the pandemic response is likely to go on months longer across the globe) cannot be met by additive manufacturing alone.

TISS recently partnered with ZVerse on a domestic supply chain initiative to meet the demand for PPE, especially face shields.

We started off by 3D printing the face shields to meet their immediate need. Next, we used injection molding to rapidly scale the project. This enabled us to meet increasing demand for these much-needed items at a price that healthcare companies could afford.

In the end, Zverse was extremely happy with the end results. In fact, their CEO John Carrington said, “the COVID-19 crisis has shown us the importance of establishing a strong and reliable domestic supply chain. TISS is an excellent partner to assist us in this important initiative.”

To this day, we have relied on this approach to help Zverse and medical device companies produce very high quantities of PPE in a fast and reliable way.

In Conclusion
3D printing and injection molding are manufacturing processes that can help bring medical plastic parts to market on time and on budget. The key is to first understand the benefits and limitations of each process for your application.

Next, follow the product development process to mitigate the risk of unnecessary costs and time delays.

Finally, partner with a domestic supplier with the capacity to quickly scale production to meet your needs in any global climate.

TISS is a premiere provider of rapid manufacturing and consultative services. Our goal is to provide a better solution from idea all the way to part, regardless of process. Contact TISS to learn more or to discuss current design and production challenges.

Brianna Gillett is an Account Executive with TISS Mold and Engineering, providing 3D Printing and Injection Molding services to clients in the southeast region of the US. Brianna has more than 5 years experience in rapid manufacturing.