I printed a number of faceshield.  I found that this, though not ideal, this has the best properties for what is needed right now: rapid print speed, ability to stack, low filament consumption, and minimum post process time.  Notes:Fasted prints can be realized with a larger nozzle.  I used a 0.8 mm.  Print time is 25 min. each.Stack prints is possible only with smaller filaments.  I would recommend a 0.4.  Peope posted success with 0.6.  However, stacked prints will reduce consume more time per frame due to the smaller diameter nozzle.  Print time is closer to one hour.  But extended walkaway time is possible.Some reported that the frames are not secure as nother options that relies on elastic for facial retention.  Recommend that people try rubberbands.  Frame may be customized to fit by heating pla with hot water.  I prefer petg for this frame because of the flexibility and strength.Good luck.   Contact me if you have any questions.Bernard Choi