# Guy Petzall

Ullapool, Scotland

A few years ago I moved to northern Scotland, where the winters are long and the nights seemingly without end. And so, in order to beguile the many hours of darkness, I began working with paper. I'd been doing origami for over a decade, but here I quickly moved on to kirigami, fascinated by the possibilities made available by interrupting the folded surfaces that origami generally likes to keep intact.

The parameters I set for myself were simple: each model should collapse flat when completed; and each model should be created from a single sheet of paper — nothing added or removed, but rather the surface of the paper rearranged without losing a shred of its area.

Life by a thousand cuts. But it does beguile those long winter nights!

Jonah10
21 x 30 x 21 cm
white paper, black card
2018

Breaking smooth surfaces into measurable chunks is one way of finding limits... but paper imposes additional limits of its own. Since the surface area of the sheet doesn't change, there's no doubling back: the functions that work best are those that have a positive y-z derivative at all points.

It's not feasible in a gallery setting, but my models also have a fun fiddle-factor: they're made for play, as they "bloom" open and collapse flat, like a good pop-up should. To see a clip of it opening and closing, visit ullagami.com/gallery or https://www.youtube.com/watch?v=R0Tz-um7MBo

The model is folded by hand from a single piece of A3 paper with nothing added or removed, with a black mount-board frame.

Lacibulb
15 x 21 x 15 cm
white paper, black card.
2019

The bulge in this model started as a sine from π/3 to 3π/2. Then I applied some gentle bezier distortions, so that the blocks grow gently both narrower and more vertical as the bulge shrinks. Increasing the horizontal "resolution" to 80 blocks results in lots of long, slender surfaces, while staggering them in diagonal stripes gives extra texture. The result is both spiky and smooth.

It's not feasible in a gallery setting, but my models are made for play, as they "bloom" open and collapse flat, like a pop-up should. To see it opening and closing, visit ullagami.com/gallery or https://youtube.com/watch?v=QY0qGSYxK6U

It is folded by hand from a single piece of A4 paper with nothing added or removed, with a black mount-board frame.