Difference between revisions of "3D printed face shields"

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We are establishing a network of 3D printer owners who can make the headbands for us. You make them and deliver them to our facility where we do the assembly and get them to the hospitals. If you want to be part of our network, fill in this form and we will contact you:
 
We are establishing a network of 3D printer owners who can make the headbands for us. You make them and deliver them to our facility where we do the assembly and get them to the hospitals. If you want to be part of our network, fill in this form and we will contact you:
  
  <span style="background:#00FFFF">[https://docs.google.com/forms/d/e/1FAIpQLSe5uMbl2USWKg6Qi6HovydA6lteBgnRsIBWnQcJaL4x6OdryQ/viewform I want to help make them]</span>
+
  <span style="background:#00FFFF">[https://docs.google.com/forms/d/e/1FAIpQLSe5uMbl2USWKg6Qi6HovydA6lteBgnRsIBWnQcJaL4x6OdryQ/viewform I want to the list for future team projects]</span>
  
 
=== What to do with the finished product ===
 
=== What to do with the finished product ===

Revision as of 21:39, 27 May 2020

Dr. Sanjay Kurani of VMC with Maker Nexus face shield
Regional Medical Center San Jose with MN face shields

Face shields are used by health care professionals to protect them when working with patients. Hospital supplies are running low. While they prefer to use commercially manufactured ones, in this emergency they are looking for alternative sources.

Visit COVID Shield Nexus for additional information on the overall program.

Overview

Front View
Side View
Top View showing wrap over


The headband portion of these shields is made on a 3D printer. If you have a 3D printer, you can make these. We have several at Maker Nexus that will be running as long as we have supplies. We deliver them to local hospitals.

In the News

Our press kit

How much do they cost?

​We give these away, paying for them from donations. We do not sell them. Promises of donations or actual donations do not affect who is prioritized to receive the PPE. The allocation team is not told who has donated. However, they cost us about $5 each to make. Donations are critical for us to be able to keep producing. We will make them until the money runs out.

Donate via Paypal to support COVID-19 response efforts by Maker Nexus.

Is there really a need?

  • We've heard from friends that "nurses are cutting up plastic soda bottles to make face shields, using saran wrap on top of N95 masks to allow for multi-use."
  • One local nurse said they are making face shields from cut up shower curtains and hot glue guns.
  • In reviewing the current design: "The nurses were over the moon about how easily the shields can be disassembled and sterilized."
  • A nurse from Marin called us and I got her hooked into the allocation process and told her they were free. She started crying on the phone. - JimS

Some photos of front line workers with Maker Nexus face shields.

See stories from those who have received face shields from us.


We are ramping up to make 1,000 a week, maybe more.

How do I get some?

If your health care facility needs face shields, fill in this form:

My Facility Needs Face Shields (click the link)

A link to Other COVID Projects

3D Print Parts At Home

Use Your 3D Printer for good

As of May 25, 2020 it appears we have all the face shield stiffeners we need. We appreciate all the work the team has done.

Sign up

We are establishing a network of 3D printer owners who can make the headbands for us. You make them and deliver them to our facility where we do the assembly and get them to the hospitals. If you want to be part of our network, fill in this form and we will contact you:

I want to  the list for future team projects

What to do with the finished product

When you have parts ready to deliver, please follow the following steps:

  1. Fill out this form with information about your donation (so we can track inventory)
  2. Seal in plastic bag.
  3. Label bag with your email, the version of face shield you printed (e.g. "MN 1.3" see releases in parts below; or "RC2" if you used that), the material printed with and the date you closed the bag.
  4. Mail to
Maker Nexus
234 E. Caribbean Drive
Sunnyvale, CA 94089

OR Deliver to us if you are local and it does not violate the Shelter In Place Order - please do not make a special trip for this - but if you are passing by on your way to get essential groceries and want to drop it off, that is acceptable - there is a box outside our front door where donated parts can be placed.

Please be sure you are following proper sanitation procedures when you bag parts - if possible, wear gloves and a breathing mask, wipe or spray with disinfectant if available. We want to minimize the chance of cross-contamination. After it reaches MN, we will be further disinfecting them before delivering to its end destination.

We have some limited amount of 1.75mm PETg, ABS, and PLA that we can give you when you have dropped off 20 or more face shields parts. Supplies are very limited so please only take some if you need it. Just ring the door bell and ask if we have any filament in stock.

3D Print Directions

Materials

Filament

These face shields are best done with PETG filament. A 1kg spool can make about 20 units. They can be done with PLA but it is difficult to get them strong enough to handle all the bending.

The face shield stiffener at the bottom of the plastic shield can be printed in PLA. A 1kg spool can make about 180 units.

Instructions

Printer Settings

Print with PETG for ease of sanitation - IPA, Hydrogen Peroxide, Bleach, and Acetic Acid up to 10% can all be safely used with PETG. If you don't have PETG, using ABS and PLA is also an approved option.

Print settings:

  • Temperature based on filament selection.
  • 3 perimeters
  • 100% infill
  • 0.3mm Draft settings in PrusaSlicer work fine
  • we are running our Prusa's at 130% speed

Parts

We use a modified Prusa design. Our headbands maintain compatibility with the placement of the pins to mount the shield. After consultation with two local hospital teams, we made several changes to the original Prusa design.

  • The shield mounting pins are moved up to the middle of the headband to eliminate a potential entry point for aerosols. When the shield is mounted to lower pins the hole in the shield is not completely covered by the headband.
  • The flex points between the headband and the "wings" have a radius added. This makes it easier to clean. The original design had a narrow angle in that area.
  • The headband is made narrower to print faster. We find that using PETG these headbands are very strong.
  • The shield has an over-the-top dome that protects against droplets falling down onto the face.

Our design is, of course, released back to the world under the same CC licensing as the original. Links to our design files are on this page.

What to print now

We have the injection molded headbands now, so we only need the bottom reinforcements of the shields. We need lots of them: the injection molding process can generate thousands of headbands a day, so we need the same number of bottom reinforcements - which are 3D printed. We need lots of them! So the focus now is entirely on printing bottom reinforcements.

This is great as even smaller bed printers can be fully utilized!

On one build-plate of a Prusa, we are able to fit 34 (might be a little bit more with more squeezing); it takes a little bit more than 8 hours, which is great for night-shifts, as there is no lost time. This also means that in optimal situations, we can get around 100 per day per printer.

GCode:

Prusa-bottom-part-plate.png

Historic

Don't look at this section for printing anything, see above about current priorities. The headbands are now fabricated with injection molding, so we don't need to print them anymore, but we need lots of bottom reinforcements.

Most important change in our headband design is that the pins are centered in the headband, so that there is something covering the shield punch, making a better seal. Also, the radii in the crevices are larger than the original to facilitate easier sanitation.

Latest release is v1.9 (2020-04-06)

This archive contains (next to the source files) the following files used used to print, which you also can download here:

  • Ready-to-go GCode: T9-PETG-Prusa.gcode (right click, download or save link as...) for PETG, T9-PLA-Prusa.gcode for PLA. This prints two headbands and two bottom stabilizers. Using print-speed of 130% on the Prusa seems to work fine. If you use ABS, please use the files below to slice for your printer. These print with little 'D-shaped' supports in front of the pins, that should break off easily.
  • 3MF slicer project file thin_shield.3mf for PETG and thin_pla_shield.3mf for PLA. This allows you to choose placement, temperatures, select which parts to print on the bed etc.
  • slice yourself thin_shield_with_support.stl (right click, download or save link as...) for PETG, thin_pla_shield_with_support.stl for PLA. There is also a no-support stl version in case you want to add support for the front-pins yourself in your slicer. If you _do_ print with build-in supports, make sure to enable the 'Detect Thin Walls' feature in your slicer.

Also please print one bottom_reinforcement.stl per headband (sometimes it is more efficient to do that separately). If you slice the version with built-in support, make sure to have 'enable thin wall detection' in your slicer. The 3mf files already have that enabled.

If your printer can't fit a headband, you can still help and print the bottom parts, stabilizing the shield plastic: Print as many bottom_reinforcement.stl that you fit on your print-bed: we need them as many people with larger print-beds focus on the headbands itself right now. Here is a plate-full-of-bottom-supports.3mf file to load directly into a slicer. Sometimes it is a good idea to use the night-time shift to print these.


More files, 3mf and STL you get directly on Github: https://github.com/makernexus/prusa-covid19-shield-remix#cut-to-the-chase-gcode-ready-to-use

Laser Cut Parts

The shields are cut from 0.020 inch thick PETG sheets. We have successfully used 0.030, it is more expensive. 0.040 is too thick and will not snap onto the headband.

PETG Sheet

One 4x8 foot sheet can make 24 shields. Our base design fits into sheets of 24"x32". If we get donations of larger sheets, then we cut it down before using it. Sheets come in different thicknesses.

  • .020 inch CLR VIVAK PETG JFM is the best. This typically comes with a protective skin on each side.
  • .015 inch PETG can be used. It often comes without the protective skins, so you will have laser cutter residue on the shield.
  • .030 inch PETG can be used with 3D printed headbands. However, for injection molded parts the shield holes have to be modified slightly or the shield will pull too flat.

We believe both APET and RPET can also be used. We are getting samples to test.

Elastic Band

Each shield uses approximately 8 inches of button hole elastic, 3/4 inch wide.

Sources

Assembly and Disassembly

Each box of face shields contains a QR Code that links to Covid-19 Shield User Instructions

Assembly

Assembly requires about 8" of 3/4 wide button hole elastic.

Disassembly for cleaning

These face shields can be taken apart for cleaning.

The sheets are made of PETG and can handle alcohol and UV. The head band and spreader could be made of PETG, ABS, or PLA. These all resist alcohol but are heat sensitive. We are not experts in how to sanitize equipment. You, as user, take responsibility for appropriate sanitization. See this page from Prusa Research for information on sanitization methods currently being tested.

A short video on how to take the Maker Nexus face shield apart

Help at MN

At this time we do not need volunteers in the makerspace itself. The space is on lockdown so that we do not introduce the virus into our work area.

Donations Needed

  • PETG filament is useful - if you aren't able to print yourself. Any color in both 1.75mm and 3mm diameter filament. It should be in a factory sealed box or in a bag with desiccant.
  • 3/4"-1" button hole elastic
  • 0.020" thick PETG film for disposable masks, sheets or rolls

You can drop-off the donations at Maker Nexus, just leave it in the box by the front door of Maker Nexus. Please use appropriate procedures when packaging - including wearing a new pair of gloves and a face mask if available.

You can also donate via PayPal towards COVID-19 efforts that Maker Nexus is working on. Donate via Paypal to support COVID-19 response efforts by Maker Nexus.

Who to contact

MN members join the #covid-faceshield channel on Slack

If you don't have access to Slack, please email faceshields@makernexus.org

External Links

Information & Discussions

- External slack for Prusa Shield discussions


Other Alternatives

We sincerely hope that all health care workers get the PPE that they need. However, in some parts of the world this may not happen. We believe the design we are using is the best for our team to make. There are, however, other solutions and we will list some here.