Assembly can be performed in around 30 minutes – depending on your skills

realistic printing time of the frame parts is around 3-4 hours

1. requirements

Please keep in mind to wash your hands thoroughly
-before and after building the mask
-before putting the mask on and after taking the mask off

materials:

  • vaccum cleaner bag
  • latex or nitril gloves
  • cable, wire or rope with a
    • recommended diameter: between 2-3mm, (tested with 2.5mm)
    • minimum length: 1m
  • 50g of PLA or similar filament

tools:

  • 3D printer – example shown with Creality Ender 3 Pro (one of the cheapest available! ~150€)
  • Scissors
  • fingernails for pushing in the wire

optional tools:

  • instead of your fingernails, you can also use something like a flat screw driver or a (not sharp!) butter knife
  • lip stick

optional materials:

  • rubber band for head strap
  • glue for more rigid frame

2. printing

  • download the most current OpenFaceMask 3D print files
  • prepare the print in the slicer of your choice.
    recommendations for PLA:

    • If you are using an Creality ender 3 (or pro) on PLA you can directly start the print using the supplied .gcode files
    • layer height can be set to 0.28mm – a coarse layer height is perfect for securing the fabric in the frame! Too fine layers would cause the fabric to loose its grip in the frames groove
    • infill can be set to anything above 30%
    • 0.4mm print nozzle diameter
    • use retraction to avoid too much stringing – this eases the cleanup after the print
  • while the printer is printing the frame, watch an instruction video on how to wash your hands: youtube

3. frame assembly

  • remove the support structures – be carefull, as the groove-walls might break off
  • clean up print on the inner latex groove. –the latex membrane is prone to puncturing!
  • click all parts together into place. If your prints don´t hold on to each other, try to tweak your print-job settings or just add some glue to the contact points. Once the filter and the latex membrane are in place, they hold the parts stronger together

4. filter preparation

  • try to cut an as big as possible piece from your unused vacuum cleaner bag
    seams and other bulk material of the bag can not be clamped down in the frame groove – use only even and flat pieces
  • match the size of your vacuum cleaner bag fabric to the frame by gently wraping it around in 2-3 directions
  • DO NOT cut the fabric into size (yet) – adding material later on is not an option, but removing is

5. filter application

this is the most difficult part

  • cut four 20-30mm long pieces off your USB cable – these will help you ease the application of the fabric
  • push in the short cable pieces at the opposing two corner areas, the nose-arch and the chin-arch: tighten the fabric along those directions.
    this ensures that the fabric is distributed evenly around the frame, and minimizes local wrinkels which might occur
  • starting from the nose part, work around the entire frame using the long remaining bit of the cable. Take out the short cables once you reach them. Try to even out the wrinkels. Too many wrinkels on one single spot are very difficult to push into the groove
  • once worked all around make sure again that the wire is pressed in all the way into the groove
  • trim the excess fabric using scissors or a cutter

6. membrane application

  • cut off the finger parts of the latex gloves, then make one cut along the shorter side – this is the largest piece of latex you can obtain from a single glove
  • same as the application of the vacuum fabric, start with the short aid-cables on four sides first. Try to already set slight tension on the membrane.
  • while maintaining slight tension throughout the application, push the long cable into the groove together with the latex membrane – remove the short aid-cables once you reach them.
  • remove the excess material using scissors or a blade. – be carefull not to puncture the membrane!

7. cutout

  • depending on the tension of the latex membrane, a clear cut out size can not be stated here
    Draw the cutout on the membrane like in the examples below – try to be as symmetric as possible
  • cut along your marking using scissors. – DO NOT stop mid through and change your path
    as the membrane loses its tension once you start cutting the hole and it also changes its shape – symmetry is restored once you complete one full loop
  • try on your OpenFaceMask:
    – is the cutout large enough for your mouth? – the membrane should end on your chin below your lips
    – are the nose-spacers still covered by the latex membrane when pushed against your face? – otherwise the mask will leak

    If the cutout is already too large… don´t worry – latex gloves usually come in pairs!

8. headstrap

  • if your cut rubber bands are not long enough you can easily combine two using a reef knot (also known as square knot)

    Von Lucasbosch – Eigenes Werk, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=17249330

  • head strap tension should be increased until the frame hits your face (usually at the nose area) or it feels not comfortable any more