Some Advice To Makers Working On COVID-19 Projects

By on March 27th, 2020 in community

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Huge plate of ventilator valves being mass produced [Source: Photocentric]

Huge plate of ventilator valves being mass produced [Source: Photocentric]

There’s been an explosion of activity in the maker community attempting to address the needs of those handling the crisis. 

This work has been a bit chaotic, frequently due to poor coordination from the top authorities in each region. As a result, multiple independent parties have attempted to organize the work with varying results. 

Like many of you, I have felt the need to “do something” and contribute. But it’s challenging to determine exactly what that “something” is. Most Fabbaloo readers have 3D printing resources available, and some have considerable arrays of equipment to deploy, and there’s a strong drive to get that gear working on the problem. 

After hearing reports of miraculous production of desperately-needed components by 3D printers in affected areas, it’s easy to get fired up and want to do the same. 

After looking more deeply into the problem and trying to determine what I could do, I encountered a number of issues that caused me to think a bit differently about the problem, and I think you should hear them. 

What Is The Actual Need?

There are plenty of reports of shortages of this or that, but it seems this varies considerably by region. Some have stocked up on certain items, but not others. Some items may be commonly short everywhere, but my suspicion is that there are different needs in different regions. Just because someone posts a request from somewhere on social media does not mean the same need is true in your region.

You don’t want to show up at a hospital with a few hundred handmade surgical masks taking many hours to make only to discover they already have a stock of 100,000 and don’t need them. Likewise, you want to be sure anything you handmake will meet the actual need, and be made to the right specifications from the right materials.

Are 3D Printed Parts Truly Safe To Use?

Many makers are never exposed to the requirements of biocompatible regimes. This is far more than just using a biocompatible material; the entire SYSTEM to produce and handle the items must be biocompatible. For example, if you extrude biocompatible filament through a non-biocompatible nozzle, the object produced is not considered biocompatible because it may have picked up chemicals while passing through the 3D printer. The environment matters, too, as well as any packaging materials used.

Some of the required COVID-19 parts actually require true biocompatibility, and I fear that proper production of them is essentially impossible for many 3D printer configurations. 

The good news is that there are in fact parts required that do not require biocompatibility, thus opening up the door to more potential maker production.

Are 3D Print Materials Suitable?

Almost all of the most common materials used in typical 3D printers are not suitable for use in a hospital due to an inability to properly sterilize them. 3D printed parts are notorious for having porous surfaces that can shelter germs of all kinds. 

But the major issue is temperature. Many hospitals use autoclaves to sterilize equipment, and this raises the temperature to levels that can begin to distort common 3D print materials, as well as dealing with the bugs.

One reader directed us to this chart of plastics sterilization capabilities, and it’s quite interesting to look through the list at the common 3D print materials. In the chart, we see the autoclave capability for each of these materials:

  • PLA: Poor

  • Copolyester elastomer: Poor

  • TPU: Poor

  • PA6: Fair

  • PA12: Poor

  • PET: Poor

  • HDPE: Poor

  • ABS: Poor

  • ASA: Poor

  • PC: Poor

  • PP: Good

  • PEEK: Good

There’s plenty more materials on the chart, but I think you get the idea: if you make something with one of the “poor” materials, it could degrade when exposed to an autoclave. This alone may limit production to only high-temperature material equipment. 

On the other hand, your hospital might not use an autoclave. Other sterilization approaches might be better for these materials. But how do you know what sterilization method is used by the recipients of your made items? 

Another aspect is water. Many common 3D print materials tend to absorb water. This can slightly distort the object’s geometry, which could be critical for precision parts. It may also make the part more difficult to sterilize. 

What Design Is Appropriate?

There are many designs for many potentially useful parts circulating. Some seem quite useful, at least with my extremely limited knowledge of medical practices. But that’s the point: most of us are 3D print people, not medical equipment designers. We could very easily design and produce an inappropriate item. 

For example, someone may produce a seemingly-useful face shield design. What if the design happens to have a sharp corner, and that sharp corner accidentally pokes a hole in a sterile glove during a medical procedure?

What else might be wrong? 

What is a good design and what is not? It’s impossible to tell unless you have someone who really knows this stuff look at it. That is the reason why the major 3D printing companies are engaging with medical design professionals and regulatory bodies to ensure the designs they promote are actually good and useful. This is usually not something an individual maker can properly do. 

What 3D Printers Are Appropriate?

Some of the proposed designs really demand specific types of 3D printers. I’m told ventilator valves have tiny internal airways with diameters of only 1mm. Could such a geometry be properly produced on a filament 3D printer? Would the layer lines disrupt the smooth flow of air? 


The point here is that 3D printers cannot produce anything; they all have multiple constraints on materials, geometry and other factors. Even worse, the requirements demanded by medical components are very high and not well understood by most 3D printer operators. The part requirements must be matched to the machine producing it, always.

Part certifications are difficult to achieve for a reason. For ex
ample, if you did produce a 3D printed part for medical use, how can you be certain it is completely free of dust and debris? What if there are internal cavities you cannot see or access? 

My Advice

Know what is actually required in your region. If you’re fortunate, someone in a centralized authority will be asking for specific items. It’s probably good advice to avoid interrupting medical professionals or manufacturers at this time asking such questions as they are busy. But if they ask you, then you know what they need. 

Leave the complex manufacturing to those who know how to do it best and fastest, and get out of their way. Components such as ventilator valves are being designed and made by larger companies that have the expertise to properly design them and the industrial equipment to manufacture them. 

Focus on simpler designs that are usable and properly producible. For example, face shields, button pushers and door openers are likely entirely suitable for production by individual makers and small companies. Personal items like door openers are perhaps not a priority in the news, but they are extraordinarily useful to prevent further infections.

Treat made objects with great care. If you do produce objects intended for use by others, be aware that you or anyone in your production line could potentially deposit virus material on the objects. It would not be a good thing to deliver infected PPE to a hospital. Consider sterilization methods or at the least leave things alone for a few days to naturally degrade the virus.

Understand the limitations of your equipment and materials and produce items that are truly usable and in demand. 

My mission here is not to deter you from helping; I instead would like everyone to reflect on what they intend on doing to ensure it is actually the best thing you could do in the crisis. Don’t be a solution looking for a problem; solve a problem instead.

Please help, but do it smartly. 

By Kerry Stevenson

Kerry Stevenson, aka "General Fabb" has written over 8,000 stories on 3D printing at Fabbaloo since he launched the venture in 2007, with an intention to promote and grow the incredible technology of 3D printing across the world. So far, it seems to be working!