Nick Allen, MD at 3DPRINTUK (London, England) says, “From the very beginning of the COVID-19 crisis, in common with numerous other 3D printing companies, we analyzed ways in which we could make useful interventions and help the efforts of the NHS. 3DPRINTUK has mastered the process of printing in PA2200 nylon using its in-house bank of EOS Formiga SLS machines. One thing we noticed was that many of the face shield-related designs were perfectly suited for FDM machines, but didn’t work well with the SLS process. As a company, we are intimately associated with SLS, and have printed over 2 million SLS prints, so we began to look at how we could optimize designs for the 3D printing technology that we use every day.”
The 3DPRINTUK team noticed the well-designed and ground-breaking Prusa face shield design had only 14 individual headbands that could be printed on the EOS Formiga P110 selective laser sintering (SLS) machine at a time, so they focused on a design that the P110 could accommodate in much larger numbers. By nesting the main peak component inside one another, they were able to create one that allowed for 260 to be printed in a single print with a 27-hour build time. See a video of the face masks being manufactured here.
Allen continues, “That is 6 minutes per shield, which is a game-changer. The design that we created clips together in 10 seconds, uses silicone straps for adjustment, can take an acetate sheet with 3 holes, is lightweight at only 42 g, and is sterilizable with IPA, autoclave, or ethylene oxide (Et0). All in all, we believe that this is the most efficient visor design to produce via 3D printing available today.”
Additional design benefits include a closed peak design for extra protection, the material used (PA2200/Nylon 12) is biologically safe, and the shape has been designed so that it can be flat-packed into an A4 envelope for cheap postage and storage.
After design proof and validation, the team members looked for production partners to scale up production. In recent weeks, they have become been directly involved with UK manufacturers working on a number of large ventilator projects, which has taken up their own printing capacity. Information relating to the design was released, and the first facility to take on the manufacturing role was Arts University Bournemouth (AUB), which had access to the P110 machine and also had laser cutting capabilities.
AUB, a top 50 UK university, produced the initial batch of 5000 units and more thereafter. These shields will be distributed for free to frontline key workers. AUB has been spearheading an effort by educational institutions to manufacture and create vital protective equipment for the healthcare sector. Since its campus closure in March 2020, the university’s facilities have become a production line for visors, face masks, scrubs, and gowns, which are being distributed across a range of public healthcare settings, including doctors’ surgeries, care homes, and volunteers providing door-to-door services for the elderly.
AUB Vice Chancellor Professor Paul Gough said, “As a specialist university, we firmly believe in the ways in which research and creativity can greatly improve productivity. In times like these, we’re challenged to rapidly innovate, and at such a crucial time, it’s hugely heartening to see those from across the creative industries maximizing PPE production through design and collaboration.”
Allen invites anyone with SLS capacity to make the face shield to contact them and they will share the design data with them. He said, “We’re sad that we will not be able to manufacture many of them in-house, but to see the project come to fruition and with such gracious and dedicated work from so many people is truly humbling.”
To read more about AUB’s production team, visit aub.ac.uk/ppe. They have printed well over 2,000,000 models in one material, and are focused on delivering the very best SLS parts possible. 3DPRINTUK are specialists in low-volume production using state-of-the-art SLS 3D printing systems.
For more information, please visit 3dprint-uk.co.uk.
Source: 3DPRINTUK press release – April 29, 2020