This is Version 2 of Protective Visor. It is inspired by erikcederb's design from 3DVerkstan. It uses a 3D
printed frame, upon which a transparent sheet material with punched holes attach to.

Changes from Version 1:

	1) Increased distance between forehead to front shield after feedback from health care professionals.
	   There are two distances, one called 'Medium' and another called 'Long'
	2) Changed hole punching template to accommodate 4-hole-punchers as well as regular 2-hole-punchers.
	3) Increase surface contact of part that touches forehead for increased comfort.
	4) Reduced curvature of part that touches forehead slightly to more evenly distribute pressure.

The main design goal of this project is to introduce stackability while retaining the original design's lightweight,
fast print times and small material use. This project was initially designed to stack on our Makerbot Rep+ in the 
MSD Makerspaces @ Unimelb. There has been further tests on a Creality CR-10 3D Printer which is closer to 3D Printers
that the community would be using.

We achieve stacking by minimising the contact surface of the top and bottom of each piece. This results in a tapered 
section. An 0.25mm gap is then introduced between each piece in the stack, now with small cylindrical standoffs at intervals.
This is to avoid slicing errors where the gap presents a 'missing layer' error.

The stack offers two main advantages:

	1) Maximising build volume in Z. Allows for long overnight prints and overall higher yield.
	2) Neater and compact packaging (if not disassembled).

Due to the tapered section nature, bed adhesions settings in slicers are a must to ensure successful prints.

In the .zip folder, we have included a single stack, a triple stack and a 16 stack. The settings used are as below:

Makerbot Print:
  - Shells (Perimeters) = 3
  - Infill = 20%
  - Infill Pattern = Diamond Fill (Fast)
  - Floor & Roof Thickness (Top & Bottom Solid Infill) = 0.8mm
  - Layer Height = 0.25mm @ 0.4mm nozzle
  - Supports = None
  - Bed Adhesion = Padded base (this is Makerbot specific and is essentially a single layer, tiny raft formed around
		   object outlines)


PrusaSlicer 2.2:
  - Perimeters = 3
  - Top & Bottom Solid Layers = 3
  - Infill = 20%
  - infill Pattern = Rectilinear
  - Layer Height = 0.25mm @ 0.4mm nozzle
  - Supports = None
  - Bed Adhesion = Raft (2 layers). Brim may speed up overall prints, but requires significant post-processing
		   to clean up.


Print time estimates are found in the Excel spreadsheet included. Please note that final print times will vary depending
on your own printer speeds and other settings. 

We settled with these print settings as it appears to give the most structural integrity to the printed piece without
increasing print times any longer.

With this latest iteration, we notice that the most bottom perimeters of each piece that is printed right above the gap
may suffer from lack of adhesion and end up delaminating from the piece. However, this has only been a single strand so 
far with all of our prints and does not appear to affect the structural integrity of the piece at all. If there are any
suggestions/findings to improve this, please contact us and let us know.

For reference to attaching the transparent sheet to the piece, please refer to our attribution and cut template sheet
for details and instructions.