A very hard action model by Jeff Beynon. The origami spring takes a lot of time because it has to be completely creased before folding.
It’s very difficult to fold into a spring, basically you have two methods: either fold each small flap, or twist a whole level so it would fall in place. I found the easiest method is folding each individual flap worked better.
Paper to use
You need one A4 format paper.