Meccano, for a prefect Crease

This great new opportunity Computer aided Paperctaft gives for a lot of Modeling, and Gizmo fun, got me thinking, why only Paper, great Media it is, there's also Plastic Sheet, and so many others...

So I came up with this Crease Rig, just some Meccano pieces, to make a slot, and a third one, to make a neat and easy Crease, on harder meterial:

It works like this:

And it folds like this:

Easy!