Ok so I’ve had a tinker, and this is what I think will work..
Instead of using the card for the hinge units, I’ve gone with fabric, because its for a laptop, its going to have a lot of bending about because of being put up and taken down. I figured the card wouldn’t last..
I’ve also added tabs at the back to attach to the laptop outer case with velcro strips. I’m going to do some artwork to cover the laptop and the shield, I may as well put advertising stuff on it as its going to be out in public..