
Photographer: Timm Gleason, Maker. Image of NIH-approved DtM model and quick print & assembly-3DVerkstan model face shields
Face Shield Update
The top ten things you need to know if you are making face shields or other PPE
This information was last updated on Thursday, April 2nd at 11 am PST.
1. Thank you
2. Top Recommendations
- If you have an FFF/FDM[1] printer and spare filament laying around:
- Locate an organization in need of PPE nearest you (www.findthemasks.com), contact them to find out which face shield and material (PLA, etc.) they prefer. Use clean handling procedures to print the frames, complete the face shield frames with a lens made from clear report covers, seal them in a clean bag inside a box, and label clearly with a date.
- Or, print and ship just the face shield frames to organizations like Operation Shields Up! (see details for which frame to print) for cleaning and distribution.
- If you don’t have an FFF/FDM printer and spare filament, consider donating any money/time you would have spent instead to support your local makerspaces and organizations who are already pumping out massive numbers of PPE and distributing them.
3. Is PPE a new type of filament?
No. Personal Protection Equipment (PPE) is a term which describes equipment used by medical workers such as face masks, face shields, gloves, etc.
4. How long will it take me to make one face shield?
Depending on the face shield design, it takes about 60-90 minutes to print a face shield frame on an FFF 3D printer. Adding in time for assembly and final bagging & boxing, you should budget 1.5-2 hours total per face shield. Some designs allow you to print two frames at once, which can speed up the process. The long print time is why face shield manufacturing is best done by print farms with several 3D printers, and one of the many reasons why you should consider simply donating money after you run through all your spare filament.
5. Which face shield frame/visor should I print?
Excellent question.
- There are currently only four PPEs, including three face mask designs, which are approved by the National Institute of Health (NIH) for clinical use.
- The NIH-approved DtM model was designed by a large team at Design that Matters in Redmond, WA in collaboration with doctors from Seattle-area hospitals. The DtM model is useful because it has an additional visor to protect the gap on top from infectious particulates (from coughing, etc.), doesn’t pinch like other face shields, and detailed research notes.
- The popularly printed Prusa face shield design (although certified outside of the USA) and many other face shield designs are still up for review. Operation Shields Up! requests donations of the Prusa shield parts, in particular the chin piece.
- You can print more at once with 3DVerkstan’s clever design (North American STL here), and simply use a 3-hole punch and scissors to form the sheet. This design has been certified by organizations, but not yet in the USA. Like other face shield designs, for areas where they have not been approved, non-hospital clinic healthcare workers may still have use for these - be sure to check with your local community before printing.
6. What sheet should I use for the lens?
There are many options for the clear portion of the face shield or “lens”. Some sources are saying to use 0.02” or 0.03” (1/2mm or 3/4mm) thick, clear PETG Sheets for the shield, and button-hole elastic for the back for some models. Other sources are saying that NIH is now allowing the use of standard US letter-sized transparencies (8.5x11 in).
However, Eric Moyer, one of the many collaborators on the DtM face shield project, pointed out that overhead sheets like Laserjet transparencies are more opaque, become even less clear with cleaning, and not as quite as clear to start as report covers. Yet, with some supplies running low, you many simply have to choose between what is currently available.
These resource links are from Joel Telling’s 3D Printing Nerd face shield video comments for sourcing transparencies in the USA.
7. What elastic should I use?
If you are assembling a model which needs elastic, please follow the guidelines of the design. Yet, although the elastic portion is too porous to clean, it is the easiest part to replace in medical settings because alternate items such as tourniquet cuffs, coband, etc. can be used.[2]
8. Who is accepting PPE?
TL;DR - Find out who and how in your local community at www.findthemasks.com
- All the feel-good articles and news videos you saw about home-grown volunteers making face shields to donate to needy healthcare workers were produced around March 25, 2020. Since then the situation has changed.
- Around March 30th, 2020 hospitals started announcing preferences on their websites for pre-certified, professionally-manufactured supplies due to sanitation restrictions. In other words, hospitals in the USA are now only accepting face shields and masks that are in unopened boxes or bags, preferring ones which are officially approved. (So if you have any of those supplies in your closet, now would be a good time to donate them.) However, local clinics and healthcare facilities are currently still appreciative of homemade items.
- Until March 27, 2020, it was difficult to tell who was accepting PPE, what the drop-off procedure was like at each location, and whether they were accepting already opened containers. Now you can coordinate with hospitals and clinics in your local community via www.findthemasks.com.
- Unfortunately the FDA and CDC have provided little guidance on the subject of 3D printing face shields, so it’s important to contact your local healthcare offices first to see what they have each decided.
- 3M, usually the go-to supplier for most of these items, is currently slammed worldwide. For additional information about possible alternatives to surgical filtering facepiece respirators, please see this February 2020 document from 3M, and the latest from 3M here.
9. What about cleanliness?
No one needs infected personal protection equipment. Here are the following measures to ensure you will be delivering clean supplies to your healthcare workers.
- Clean your machines prior to manufacturing.
- Wear a face mask and gloves while handling everything.
- Bag the products and leave them for several days (several sources are citing 3 days[3]) before donating to ensure no contamination.
10. Organizations Needing Your Help
These organizations need money and volunteers (of all types: legal, accounting, managers, etc.) to support the effort of designing, producing, and distributing PPEs for free, to healthcare workers who need them.
11. What if I have a resin printer (Formlabs, etc.)?
Summary: Donate/loan your Formlabs printer to your local hospital for printing nasal swabs.
Considerations
WeWork Labs Seattle contacted me on March 31st, 2020 because they wanted to help out by 3D printing face shield frames on their Formlabs' Form 2 printer ($2850 for a refurbished one). We also discussed cutting transparencies on their Glowforge printer ($2495 for a basic model). I’m not an expert, but here are some of the considerations I proposed, using my company’s product experience for The Cyrcle Phone as an example, which might help you in your own decision.
- Resin printers excell at printing models at higher resolution. This (and the fact that the clear resin is more clear than the resulting clear filament print) is why we love to use the WeWork Labs Seattle Formlabs Printer to print and examine our smartphone enclosure prototypes designs.
- Resin is generally more expensive than filament.
- Formlabs Clear Resin (1L) $149.00
- The Cyrcle Phone enclosure, front = 13.21 mL
- The Cyrcle Phone enclosure, back = 12.69 mL
- Total = 25.9mL x $0.149/mL = $3.86
- Tactink Clear Filament, PLA Filament 1.75mm, (1kg) $15.59
- The Cyrcle Phone enclosure, front & back = 31.93 g
- Total = 31.93g x $0.01559/g = $0.50
- The resin printer bed is generally smaller. Of course you can print the face shield at an angle using support material. But this seems wasteful when you can print a face shield flat on a $300 FFF printer like the Ender 3 with inexpensive filament.
- Resin printers are excellent at printing smaller items, such as the much needed nasal swabs for COVID-19 testing (3D files) However, we do not have the necessary sanitation equipment, nor the specific resin on hand at our WeWork Labs Seattle.
- We could print door openers, but who are using those during WFH?
- Loaning the Formlabs printer to a hospital might be the best idea yet. On April 2nd, 2020, Formlabs hosted a “Live Session”, where Formlabs Director of Healthcare Gaurav Manchanda walked through the ongoing production of test kits and PPE on Formlab printers. One of the listeners suggested donating his Formlab printer to his local hospital so that they could make the nasal swabs, since the hospitals meet the sanitation requirements.
- Formlabs has been leading the way with procedure documentation. See their April 1, 2020 webpage, Things to Consider to Produce Safe and Effective Medical Devices
- The Formlabs website also has two face shield frame files available for download and print. https://formlabs.com/covid-19-response/covid-face-shields/
- Isopropyl alcohol (IPA) supply is dwindling, and used in the resin curing process. Some IPA alternatives are possible. Formlabs did a Twitch video earlier this week with some at-home tips & tricks on how to clean parts without IPA. Long story short, soap(normal dawn dish soap) and water can be a really solid workaround. Tripropylene glycol monomethyl ether (TPM) and Yellow Magic 7 also dissolve liquid resin.
[3]I have not yet found research to support if 3 days is long enough.