16th April 2020

A huge thank you is deserved for all those getting in touch and supporting the NHS, medical, and care centres with their valuable work protecting lives. The response has been overwhelming. The South Devon College based 3D printing group has been working hard to respond and currently have supplied over 350 units to the NHS. Additionally, over 100 have been donated to local medical and care centres.  Furthermore, a delivery of over 250 units is planned for this week. All of this has been completed whilst observing the strict government guidance of social distancing and limited movement.

The response from the local community continues to be heartwarming with Crispin Associates, Darthaven Marine, Hercules Hydraulics, Partington Print, and Ecomotus, amongst others, continuing to donate physical resources, time and money to allow the College and wider team to increase the number of 3D printers and materials for each element available. As well as members of the local community using home-based printers, local hi-tech companies including Dart Valley Systems, Teignbridge Propellers and Gooch & Housego have helped to provide an increased number of visors.

The Hi Tech & Digital team at South Devon College has been working with our colleagues at the NHS over the last week on a few modifications and additions to the visor assembly.  This is still based on an open source file, but now includes modifications that allow the headframe some more flexibility, provide a top shield cover and some additional clips to secure the shield.

If you want to get involved in producing units, there’s a breakdown of the parts created and some guidelines and tips on how to produce the face shields yourself.

There are three key elements to the visor (1-3) plus two optional parts: (4 & 5);

1. The bracket (or headframe) that attaches to the head with a separate bottom reinforcement.
2. The clear visor screen (A4 size with hole punches that allow attachment to the bracket – template is shown below).
3. The cord/elastic that is used to tie and secure the visor in place.
4. The shield cover to protect particulates when working at a 40-degree angle
5. 3 x Clips to hold the shield to the bracket (or headframe)

Some basic guidelines and tips;

For Fused Filament Fabrication (FFF) or Fused Deposition Modelling (FDM) 3D Printers, using filament reels, current settings are for PLA, ABS, PETG (material)

Guidelines for bracket (or headframe), separate bottom reinforcement and shield clips slicer settings;

• 0.4mm Nozzle
• Minimum 5% infill
• Shell thickness minimum of 2
• Layer height of maximum 250 microns or 0.250mm
• No Supports or Rafts
• Between 1 hour to 1 hour and 30 mins run time per unit for Headband and 20 mins to 30 mins run time per unit for the bottom reinforcement (as a combined print of both headframe and bottom reinforcement can have a run time of 1 hour 30 mins to 2 hours, depending on speed, feed and type of printer).
• Clips take under 5 minutes to print 3 clips for one headband. You could print these as batches of higher quantity.

Guidelines for shield cover slicer settings;

• 0.4mm Nozzle
• Ideally using VASE Mode Infill, or 0 to 5% infill only.
• Shell thickness minimum of 2
• Layer height maximum of 250 microns or 0.250mm
• No Supports or Rafts
• Using VASE Mode the print time is between 20 to 35 minutes depending of speeds and feed rate. Using 0 to 5% infill print time is between 40 to 55 minutes depending on speeds and feed rate.

 

For your information the link to the original source file is:

https://www.prusaprinters.org/prints/25857-prusa-protective-face-shield-rc3

Any other technical specifications can be provided on request.  If you have any questions, please contact Steve Caunter at [email protected].