Here are links to a face shield system I designed. It's key features are:
The shield is held in place with a friction fit so it does not need to have holes punched in it. This is great for quickly changing shields instead of having to sterilize the whole unit each use.
It can use a range of materials for shields but is designed for regular laminator pouches, either 3 or 5 mil. Usually about $0.30 each.
The brow strip has a compound curve to make it very comfortable, even for extended periods.
The retainer for the elastic head band is infinitely adjustable.
I am just finishing up a removable cover that clips across the top to reduce the chance of particles falling onto the face. Clips off for easy cleaning.
Feel free to create and share but please do not charge money, other than for supplies if you need to.
V4 Bottom.stl
V4 Head.stl