Open Source High-Temperature RepRap for 3-D Printing Heat-Sterilizable PPE and Other Applications

Abstract

Thermal sterilization is generally avoided for 3-D printed components because of the relatively low deformation temperatures for common thermoplastics used for material extrusion-based additive manufacturing. 3-D printing materials required for high-temperature heat sterilizable components for COVID-19 and other applications demands 3-D printers with heated beds, hot ends that can reach higher temperatures than polytetrafluoroethylene (PTFE) hot ends and heated chambers to avoid part warping and delamination. There are several high temperature printers on the market, but their high costs make them inaccessible for full home-based distributed manufacturing required during pandemic lockdowns. To allow for all these requirements to be met for under $1,000, the Cerberus – an open source three-headed self-replicating rapid prototyper (RepRap) was designed and tested with the following capabilities: i) 200oC-capable heated bed, ii) 500oC-capabel hot end, iii) isolated heated chamber with 1kW space heater core and iv) mains voltage chamber and bed heating for rapid start. The Cereberus successfully prints polyetherketoneketone (PEKK) and polyetherimide (PEI, ULTEM) with tensile strengths of 77.5 and 80.5 MPa, respectively. As a case study, open source face masks were 3-D printed in PEKK and shown not to warp upon widely home-accessible oven-based sterilization.

Unlocking the surge in demand for personal and protective equipment (PPE) and improvised face coverings arising from coronavirus disease (COVID-19) pandemic – Implications for efficacy, re-use and sustainable waste management

“…A limiting factor in the production of alternative biomaterials for alternative to single-use PPE relates to thermal stability of materials for fabrication and potential for deformation due to thermal processes. Skrzypczak et al (2020) recently reported on a new 3D printing approach for meeting such a need where they described an affordable, self-replicating, rapid prototyper that would also make this approach more accessible to home-based 3D printing activities. Chen et al (2019) also demonstrated potential for exploiting different forms of polymer processing (such as 3D printing and injection moulding) after novel vapour hydrogen peroxide and electron beam treatments that could be advance next-generation PPE and medical device technologies.…”

Overcoming Supply Chain Disruptions During Pandemics by Utilizing Found Hardware for Open Source Gentle Ventilation

“…If the device is used on multiple patients, the pump and hose should be sanitized with ethylene oxide if made of silicone materials [52] or steam for fluoroplastics [53]. As 3-D printed components are very porous [54], they can be hard to sanitize fully, and therefore a new mouthpiece should be used for each patient unless printed in hightemperature plastics that can be sterilized with heat [55].…”

Conversion of Self-Contained Breathing Apparatus Mask to Open Source Powered Air-Purifying Particulate Respirator for Fire Fighter COVID-19 Response

“…Distributed manufacturing of open hardware has been shown to be an effective means to meet demand for a wide array of medical supplies during this immense supply shortages observed in the current pandemic [104][105][106][107][108][109][110][111][112][113][114].…”