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3
Introducing the V-fold
This is a simple but versatile mechanism. The pop-up images are attached to the page by means of V-shaped flaps or an inverted V shape, depending on the effect you wish to create. You apply glue to the underside of the tabs and attach them to the backing sheet so that the point of the V touches the central fold line.
If the angle of the V is 90°, the pop-up will stand vertically when the page is fully open. If the angle of the V is less than 90°, it will lean backwards, but if it is more than 90°, it will lean forwards. You will need to experiment with the position of the V on the page. If it is too near the front or the back the image may stick out of book or stop if from closing.