Flat Pack Face Covering Kit / Fabric Mask. Fast Batch Stack Print by FullPlasticScientist

Last crawled date: 3 years, 3 months ago

For the transparent 'Eye Cu Smile' variant see https://www.thingiverse.com/thing:4598055
Alternative sleeker ribs STL files can also be found in the transparent variant listing.
This is a face covering flatpack frame system that has been optimized by a Manufacturing Systems Engineer for mass manufacture on a Delta 3D printer.
Based on features optimized from the following designs:
University of Delaware ‘Hens Nest V3’ https://me.udel.edu/hensnest-3d-printed-face-mask/
2ROBOTGUY ‘Community Mask Frame’ https://www.thingiverse.com/thing:4231792
Ctwiles 'Mask Frame "CEG Extreme" and Small n95 fitter, https://www.thingiverse.com/thing:4262131
Checho3d ‘Mascarilla Hermetica’ https://www.thingiverse.com/thing:4246855
De_Giusti_Design ‘ergonomic mask seal’ https://www.thingiverse.com/thing:4365161
AaronBinstock ‘Mask Frame (Remix)’ https://www.thingiverse.com/thing:4271694
boring_pilot ‘Tyvek soft facemask’ https://www.thingiverse.com/thing:4257706
Mike ‘RC3 Stack - High Speed Print’ https://www.prusaprinters.org/prints/30194-rc3-stack-high-speed-print
I made this design due to the recent attitude and law changes towards the wearing face coverings in public in the UK. They cost very little to make and hence can offer them out to those still struggling in our community on mass. This is face covering designed not for maximum protection but instead for maximum impact. Give the public face coverings that seal, are comfortable long term and they can use any breathable material lying around. Cost is no longer a barrier to having a comfortable and somewhat efficacious, if only in protecting others, face covering. Too many are at the end of their rope financially and the cost of face coverings just to go buy food is one more burden they now have to bear.
Designed for batch manufacture in large stacks of 50 or 100 components in 1 print job so I can make 50+ a week on a Delta printer. I wanted to make masks in pla such as the Montana but the risk of injury is too great. Additionally I couldn’t stack the traditional mask designs for mass manufacture. Hence why I settled for a flatpack skeleton frame design that orientated PETG frames 90 degrees to the face and relies on donor flexible material for the main structure.
Assembly instructions included as pdf
-Key design features-
Comes with detailed assembly instructions, see attached pdf file.
Uses any breathable filter material. T shirts, hydroknit or hepa air purifier material dependent on users needs and desired level of filtration. See University of Delaware hens nest mask recommendations for best practice and advice I've found so far regarding filter material options. I provide them with dual layer hydroknit shop towels as standard for a cheap basic level of protection.
Holds material away from the nose and mouth for long term comfort.
Flexible wireframe design that conforms to the face when printed in PETG. Can be made to seal effectively to the face due to conformal design.
Can be printed in stacks of 50+ components in one print job using Cura bridging settings
Uses thick 20mm elastic in the same style as professional half face respirators. No knots needed just pull to adjust. Thick elastic means its more comfortable for long term use and offers finer levels of adjustment.
-Wireframe methodology-
Each component was designed from scratch in fusion 360 to make a solid part using wall/shell printing only. 0% infill and no top or bottom layers. Hence the STL files do not look like the final parts until they have been sliced. To see how the parts should look once sliced see attached printing guide pdf. Wireframe wall only is often employed for face shield manufacture. By printing wireframe, retractions and hence blobs are reduced and the part is made of continuous thick and strong strands of plastic. Splitting stacks also becomes far easier as there will be less raised blobs and strands of plastic to cause a knot in the bridging layer between parts which subsequently can fuse them together and cause stacks to fail.
Optimized for 0.6mm nozzle and 0.3mm layer height. Produces thick and durable layers with good adhesion quickly for mass manufacture.
See attached PDF for detailed print settings guide.
Wall/Shell counts with a 0.6mm nozzle and linewidth for each part:
Face frames - 6 walls
Elastic frames - 9 walls
Retain Frame - 5 walls
Ribs - 2 walls
For a 0.4mm nozzle these settings may work but I have not tested them
Face frames - 10 walls
Elastic frames - 14 walls
Retain Frame - 8 walls
Ribs - 3 walls
If these settings don’t work then play around with line widths and wall counts until you get a part with only continuous lines at various points as shown in the attached print settings pdf. You want to avoid unnecessary retractions and blobs that can fuse the stack layers.
The design relies on the inherent flexibility and tendency to creep of PET G rather than crack like PLA over time. Hence can tolerate distributed elastic loads well if printed in continuous looped wallls in the direction of the force applied.
The frames are likely to break after a few uses if using PLA. I cannot recommend PLA and would stipulate that only PETG or other durable and flexible filament types are used. Such as copolymer blends. For PLA I advise printing the 'Community mask frame' instead.
-Cura bridging settings for printing stacks-
If a 0.3mm, 1 layer, gap is left between parts as with the stack stls provided then bridging will be activated in Cura if enabled. This allows you to slow down the first layer of the next part and aggressively cool it so doesn’t bond to the layer/part below.
See print settings PDF for guide of how to tune these settings.
-Stacking parts-
1, 10x and 30x part stacks stl files provided. If you want to make your own custom stacks just combine multiples of the 10x stack separated by 0.3mm in the Z direction. For a guide on how to stack parts in different slicers see 3D printing nerds stacking guides on Youtube.
-Sterilisation procedures-
You must follow Prusa sterilisation guidelines when packing protective equipment. Our standard procedure is as below and we pack into a4+ size heavy duty zip lock bags containing instructions, hydroknit towels and elastic.
Act as if you have COVID. Wear gloves and a faceshield as a minimum. Preferably a mask as well. Work in sterile conditions. Individually bag in zip lock bags immediately after sterilising. I use Ethanol (surgical spirit) bath as per PRUSA sterilisation guidelines. With date of packing prominent on the first page of the info pack. Other options such as alcohol, UV-c light, weak bleach solution also a sterilisation option. Do not autoclave petG.
PRUSA advice on packing faceshields that also applies to the PETG components of this kit:
"If you want to manufacture shields for others PLEASE READ THIS CAREFULLY
Act as if you were infected by the COVID-19 virus.
Wear a face mask and a fresh pair of gloves when collecting each batch of printed parts. Store the parts immediately in a sealable bag.
Talk with whoever you’re making the shields for, let them know about your manufacturing environment
There is still debate about how long the virus survives on plastic, but most sources mention 2-3 days. That means that by letting the packed face shields sit for 2-3 days before distributing them, you’ll greatly reduce risk of transmission
Do not store the entire stock in one place, minimize the risk of cross contamination"
Source Josef PRUSA
-Licence and selling of face covering kits-
We share these files under non-commercial licence. It would be great if you donated these face covering kits to those in need for free. If you need to cover your production costs, we are ok with you selling the face covering kits for production cost. However, we do not want to see these kits on eBay or amazon for extortionate costs. The design is open to the community for modification and improvement. You do not need to accredit me with the design. I just want to get it out there for others to use and improve upon.
-Legal-
Use
Recipients of the flat pack face covering kits are responsible for using their own judgement before deciding to order, receive, distribute and use these flat pack face covering kits in any setting. This flat pack face covering kit can play a part in reducing risk to users, but they are responsible for following established government and their institutional guidance as to how to protect themselves from COVID-19. These flat pack face covering kits are disposable single use only. Discard after use. Do not reuse or re-sterilise. It is expected that these flat pack face covering kits will be used as a last resort in conjunction with eye protection in accordance with the relevant guidelines. Flat pack face covering kits are not a replacement for or negate the need for users to stringently follow the recommended hygiene practices or other relevant guidelines. Recipients of these flat pack face covering kits are required to provide a copy of this disclaimer to any third party before distributing them further.
Production & Certification
These flat pack face covering kits are made to a common design but are made from various brands of PET-G plastic and on multiple types of 3D printer. This type of frame based face covering kits are widely used in large numbers around the world to combat the coronavirus pandemic. However, the face covering design supplied in this pack does not have regulatory approval. Hence these flat pack face covering kits are considered for temporary emergency use only when no other PPE is available. Potential users should consult their guidelines and procedures regarding the use of non-standardized PPE before using these flat pack face covering kits. The plastic of the frames has a limited lifespan and will degrade with successive use, hence they should be viewed as temporary and disposable.
Limitation of Warranty
No representation, promise, express warranty or implied warranty concerning the suitability of these flat pack face covering kits for any medical or personal protective use including, without limitation, their effectiveness to filter, block, or protect against any pathogen and particle, including COVID - 19. The kit is provided in a good faith charitable effort to help with the COVID-19 pandemic. If you use this design, you agree to comply with any government or institutional guidelines. You also agree that the designer: (1) Disclaims any warranties related to fitness of use, non-infringement, or compliance with regulatory standards; and (2) Have no liability for any claims of any kind made by person, either as a result of use of or as related to the item.