First I just want to say that I genuinely feel for everyone affected, whether frontline healthcare, long term patients whose care is impacted, parents, children, employers, employees,….

Hell, its affecting everyone !

Fishy Filaments as a company is helping where we can, but our material is not medically rated and our own 3D printing capacity was built as a quality test lab not a production facility. The current 3D printing community focus on disposable face shields is not where we can help most. Our site is not clean enough, its not big enough and we don’t have printers that are able to make a difference. But that is enough ‘nots’ !

Instead we’re mobilising our wider innovation capacity to support others to take advantage of the material in ways that we can’t, and we’ve logged our raw material production capacity with both the UK and UN innovation efforts, should they need to start to use non-medically rated materials.

But mostly we can think about the specific environments that our material might be used in by others, either as 3D printed forms or injection moulded forms, and where its engineering and chemical properties are useful rather than in areas where there are specific needs for justifiably high levels of certification.

We don’t want to distract effort away from frontline energy or focus in healthcare, but we do want to help if we can.

Where we are right now

Key properties of our material are its ability to be boil washed and to be bleached, and we’ve been approached by a lab within a major research hospital in Canada, called McGill University Health Care, to help them explore uses, away from the front line, but where healthcare supply chains are subject to disruption.

They have a number of desktop 3D printers that they use within their lab and have been struggling to find a material that meets their needs. Their team found us and we jumped at the chance to help.

After some discussions and some rapid learning on our part, the key challenge would appear to be that few 3D printing materials can stand being sterilised in conventional healthcare settings, and those that can require a high degree of skill and infrastructure to use. Even general use applications, such as the button pusher we recently showed, whose materials are not required to hold medical certification are now requiring more extensive washdown, and that means they need to be made to be deep cleaned.

We know that we can boil wash thin-walled 3D printed forms made from Porthcurno and retain water tightness. This is especially effective in single wall vessels since the coherence of interlayer adhesion is very much more predictable than that seen in thicker wall models. The way that FDM-type 3D printing works means that most prints have what is known as ‘porosity’; gaps and voids where molten material has not been laid down, and that can hold air or other materials if those pores reach the surface of the form. A single wall, well printed in a strong material can be just as effective a barrier to water or gas, as a multi-layered wall, with all its imperfect alignments and pores.

Translucent base

Translucent base

The questions for us are then; whether there are applications for 0.4-1.5mm thick, water tight forms that can withstand boil washing ++, and if there are does it make sense for them to be 3D printed from our material ? Those forms can printed and then be tested in sterilisers that operate using steam at 120C (not 100C of a liquid water boil wash) to make sure that they do retain coherence and enough dimensional accuracy that they remain useful. McGill will find those applications and we, with the manic skills of 3D Printing Cornwall, will help them print forms suitable to test. Realistic testing is essential, especially in a crisis-driven R&D setting.

Challenging Tests (tautology?)

As mentioned there are areas where we think tests will be challenging.

  • We have yet to test against partial pressure sterilisers, where steam is vented into a chamber that has been partially drained of air, and we expect this to be a difficult environment for 3D printed forms to withstand. The partial vacuum means that the forms must be printed with 100% infill (so no holes or internal voids filled with air) because any trapped air could explode through the form.
  • Directional steam blasts in sterilisers will cause differential heating of forms and might increase the potential for delamination (splitting), so the print quality must be high as well as the material being strong.
  • While we have bleach washed our material, we don’t have access to the same cleaning materials as McGill uses. Our nylon is chemically resistant but this still needs testing.
  • The underlying technique of FDM means that the surface of 3D printed forms is often ridged, even when completely sealed and water tight. This offers micro-shelter from some cleaning technologies, so the forms might need to be ‘over cleaned’ to compensate. Multiple cleaning methods sequentially used could offer some proceedural challenges, such as placing hot forms direct from a steriliser into an alcohol bath causing evaporation of dangerous fumes and rapid temperature changes.

What Next ?

Our raw material is strong enough, but can we get to the point where low cost desktop prints are reliable enough to represent a genuine opportunity to replace components that need deep cleaning (remember, away from intimate contact or medical applications where we aren’t rated for use) ?

Crisis innovation presents severe new challenges but it does not give us a free pass to experiment with no consequence. On the plus side it brings together new partnerships and forces us to be open to futures that we hadn’t considered before.

Good luck everyone and Stay Safe !