I tried printing JPoel's original design but I ended up getting a piece of filament jammed in the hinge.
Rather than adjusting the print files myself to make the filament hole larger I thought "why not just print the hinge in the design?" (think Flexi-Rex). So this is the result - a simple printed piece is that 100% ready to use when done. The design has a 0.5mm gap between the hinge components which should be enough even if you have a significant amount of elephant's foot.
The print size is approximately 228 mm x 98 mm. I've also included a "blank" stl for people that want to customize their prints.
*Edit 1: Added a "r4" file which extends the length of the hinges to remove the gaps. The effect is shown in the picture with the bold green stand.