tessellation

Diagrams: The Zipper Tessellation and Variations

Issue Number:
12
The Zipper Tessellation is a good starting point for many variations, such as the Zipper Ring and Vase, presented here with crease patterns and some diagrams.

M.C. Escher has been a great source of creative inspiration for me. For a long time, I have tried very hard to capture his never-ending stairs (from Ascending and Descending, 1960) in a tessellation but have yet to succeed. However, in my pursuit I managed to capture some essence of the question "Is it going up this way or that way?" raised by Relativity, 1953, as can be seen in my Zipper Tessellation above. From this stating point, I was able to find several variations, each one made from a single sheet of paper. Two such variations are circular: a Zipper Ring and a three-layer variation each shown below.

All three models are minor variations on the same pattern that range in difficulty. Let's begin with the simplest, the Zipper Ring, which is not a regular tessellation, but is easier to collapse than the flat version. You can find full diagrams for this model here. From there, try to make the three-layered version as an extension of the ring, comparing the original ring's crease pattern to that of the three-layered version. Achieving this, you can try the original Zipper Tessellation, which is much harder to collapse. Note that you can collapse it either flat or in tubular form. Two additional variations, my Zipper Vase and "Go THIS Way!" tessellation are shown below. You can find crease patterns and assembly discussion for these last three in this document. I do hope you enjoy folding these. Just try not to get disoriented!

-Ilan Garibi

Tessellations and How to Get Started

Issue Number:
10
Tessellations have become increasingly popular in origami. But it's not always easy to get started. This article introduces some videos that can help you on the way.

In recent years there's been a great buzz around a new area of origami: tessellations! Essentially, these are patterns you fold and which you can repeat over and over, extending the design. In other words, it is a tiling.

But this article isn't so much about what tessellations are. If you'd like to know more about that, David Lister wrote some essays, which give great background information and an interesting insight into the history of tessellations: Part 1, Part 2, and Part 3. Ilan Garibi also wrote an article classifying tessellations, going into the creation process, as well as giving tips on useful tools: Tessellations: A Brief Theory of Warping Paper (TheFold Issue 2).

While designers such as Yoshihide Momotani and Shuzo Fujimoto explored tessellations early on, only recently did these folds become more main-stream. With it an explosion of stunning designs have emerged.

As is usually true for a new area of origami, great pictures started to appear, but folding these tessellations remained a bit of a secret for some time. Then crease patterns were shared, but these aren't well understood by everyone. The first big publication (in English) that demystified tessellations and explained how to fold several stunning projects was Origami Tessellations by Eric Gjerde (also available at The Source).

Still, the learning curve for folding tessellations is steep for many, sometimes too steep. Although Eric Gjerde's book is fantastic, it does require good basic origami skills and perhaps a love for working out the details yourself. This is why I decided to make a bunch of instructional videos, which help a bit with those details. For starters, I presented some origami tessellations step-by-step. It's perhaps the easiest way to get going if you already folded other non-tessellation models, be it from video or diagrams.

But the true magic of tessellations lies in creating your own designs and patterns and how easy it is compared to designing representational origami. You can start experimenting: fold a grid and then see how you can collapse the grid into shapes and continue on. At least at first, it's probably better to concentrate on structures that do fold flat, although tessellations with 3D components are definitely possible and have a beauty in themselves.

Or, if you aren't so much about experimenting in the wild, you can learn about some basic rules that will apply to all tessellations. Knowing these rules opens you a whole world of exploring tessellations. I myself was introduced to these rules by Ilan Garibi when I met him at the CDO Convention in 2010 (in Italy). I then made a video, lovingly and jokingly calling it a "Tessellesson". It demonstrates the technique on a model called "Bricks" by Ilan Garibi, which works on a square grid. But the rules can be applied to other grids and in particular also triangle grids.

(There is a longer version of this video here)

And once you know the rules, all you need is some "molecules" that you want to use and combine to construct your crease pattern to collapse. You can either - as before - experiment to come up with some of these. Or you can use techniques others have already explored. Some of the more common techniques I have presented in short videos. In particular, here's a playlist on techniques that work on a triangle grid, and which are also presented in Eric Gjerde's Origami Tessellations:

Once you master these techniques you can use them in two ways: either to create your own designs by combining them; or simply to understand how to collapse crease patterns of designs others have come up with and shared. For example, Eric Gjerde has posted some crease patterns on his website http://www.origamitessellations.com/, as have many others on their websites or Flickr albums (e.g. Andy Wilson, Christiane Bettens, Ilan Garibi, and Melina Hermsen, and Ralf Konrad). Anna Alekseeva put together a set of pictures classifying different tessellations according to their wallpaper group. Another great resource is Alex Bateman's website. It not only includes crease patterns, but also a program, with which you can create crease patterns for tessellations.

And if you want to see extraordinary representational work with the use of tessellation techniques, do check out Joel Cooper's website or his Flickr album - in particular his masks.

With that I wish you happy folding and exploring the world of origami tessellations!

Tessellations: A Brief Theory of Warping Paper

Issue Number:
2
This article gives a nice overview of the types of tessellations there are, and how to create one yourself.

Tessellations are the new trend in the origami world. Definitions, which, by definition, try to draw definite border lines, can only do injustice to this field. There are Corrugations, Molecules, Curved Tessellations, and so many other subcategories. Here is my humble addition to this field.

First, let's define the types of tessellations. I am not familiar with any formal definition, even Wikipedia leaves this term unexplored.

Types of Tessellations

I like to divide the tessellation world into 4 categories:

1. Classic
2. Corrugation
3. Recursive
4. Back & Forth AKA Organic tessellation

Classic

"Red Flower" Tessellation designed and folded by Ilan Garibi, Tant

The Classic is, well, classic. Since Fujimoto, a Japanese origami master who published books that included origami tessellations in the 1960s till nowadays, this is the most common type. It's based on two major grid types - the Hexagon and the Square. It is made of Molecules that can be spread in all four (or six) directions, covering a continuous surface. By nature, the surface of the final model will have an odd number of layers (one, three, five, or even more) throughout. This is because whenever the paper is first folded this way, it must be folded the other way, too, to allow continuity. This change of number of layers gives the most amazing effect when you backlight your model. One layer is a bit transparent while three layers and more are dark. For that reason one tessellation can give you four models: first side, the other side, and both sides backlit.

Corrugation

"Diamond Corrugation" Tessellation designed and folded by Ilan Garibi, 40gsm Kraft paper

Borrowed from the English dictionary, a corrugation is: a wrinkle; fold; furrow; ridge. This type of tessellation has no triple or more layers. The entire original surface of the paper is visible to the eye, and the pattern is usually in the form of waves. There is no point in using backlighting on this type.

Recursive

"Hydrangea" designed by Shuzo Fujimoto, folded by Sara Adams, Dreamy paper

Recursive tessellations are unique. The concept here is to make the same fold in a smaller scale on one square in a repetitive manner. A classic recursive model is the Hydrangea by Fujimoto.

Back & Forth, or Organic tessellation

"Wave" Tessellation designed and folded by Ilan Garibi, Elephant Hide

Last in my list is the group of folds that are simply done this way: one row folded back and two rows are folded forth. Repeat.

Taking it Further

Of course, you can combine several types of tessellations in one project. For example, you may want to use a classic tessellation to form a border for a recursive central piece (left), or use a recursive tessellation as a molecule for a classic tessellation (right).

"Windows" Tessellation designed and folded by Ilan Garibi, Elephant Hide

High density tiling of the "Hydrangea" by Shuzo Fujimoto, folded by Sara Adams, Rainbow Kraft paper

More examples

This video shows further classic tessellations:

Creating a Tessellation

Tessellations are usually folded in three steps only: Grid, Precrease (all other folds than the grid) and collapse. Each step has some basic know-how and many tips, but before elaborating on that, we have to discuss the single molecule - the core of the model.

When I try to create a new classic tessellation, I follow the Way of the Molecule. A molecule is one unit of the tessellation: the repetitive part. I try to find an interesting molecule that follows two very simple rules:

1. Can I make a fold that has all of its sides (or, at least, every two opposite sides) to be totally the same?
2. Can I make sure all the original edges of the paper will stay on the edges of the folded molecule?
If this happens, you can tessellate this fold. To understand this concept let's take a look at the simplest fold - an unfolded square paper. All the original edges of the paper are on the edge of this molecule, and all four sides are identical. We can spread this molecule to all 4 directions, endlessly.

Moving to real molecules, let's start with only two square molecules. A trick for checking whether they can be tessellated is to glue-tape the edges together. If you can spread the folded molecules to their original flat state, align them and put a cellotape to hold them together, and then collapse the combined units, why cut the paper in the first place? Now start with a 1×2 rectangle of a paper, crease all needed creases on both squares, and collapse without the need for a cellotape.

For a better example, take the basic twist fold (the base of Kawasaki Rose). The pattern on all four sides is the same; hence you can put two molecules one by the other, unfold the common edges and tape them together. Now collapse both of them to get your first 1×2 molecules tessellation. Again, if we can tape two, why can't we start with two connected squares, in other words a rectangle of 1×2 proportions? Do all folds on both squares, and collapse.

Note that the twist direction had to be changed on the second molecule, to allow continuity.

These are simple rules, yet they are probably sufficient to make all classic tessellations.

Creation

To create a new molecule (for a Classic or a Recursive Tess) all that's needed is to follow two pieces of advice: Dare and Play. Dare to doodle with paper, grid it, mold it, and then try again. And again. It works for me.

A tip for this section - having a molecule that applies to the rules may not be enough. There is a third request - it must be collapsible. To make sure it is so, first try to collapse your molecule on a 2×2 tessellation, and then on a 3×3, which have the center molecule bordered by other molecule from all 4 sides. If those two tessellations can be collapsed, you can go to larger numbers.

Originality

Do not feel bad if you came up with this marvelous model, just to get a remark on your Flickr page, saying: "Oh, I did that a year ago, see it here...". This field of creation is very mathematical and many people discovered the same model independently. Enjoy your power of creation, even if you are not the first!

The Grid

Tessellations are usually made from grids. Divide the paper to 32 equal parts on both directions to get a 32×32 Grid. 16 grids may be good for beginners, and 64 grids will bring an amazing effect and finger aches. Common grids are the Square and the Hexagon (which includes the Triangle grid, since we all fold our hexagon by making six triangles). More rare ones are the Rectangle, usually 1×2 proportion, and the Diamond:

Making a grid may seem trivial, but the truth is far from that. My first tip is always doing your creases bi-directional. It is a double effort, but it is often very helpful in the collapse phase.

Now, to get a 2×2 grid, you need one horizontal crease and one perpendicular to it. That's easy to do - just divide into half in both directions. To get a 4×4 - divide all halves into quarters. Still easy - this is a cupboard fold, actually. Going to 8×8 starts to be problematic - getting the first 18 line is easy - fold the edge to the 14 line. But how do you get the 38 line?

One solution immediately pops up - fold the edge to the 34 line, which divides this length to 38. This may be good for a 8×8 grid, but not that good for a 16×16, lousy for a 32×32, terrible for a 64×64 and disastrous for a 128×128 grid. The reason lies in the fact that every crease shrinks the paper a bit. When you fold the edge to the 4664 line to get the 2364 line, the distance of the 46th line is not 4664 of the paper, but shorter than that. See this full sheet of Elephant Hide after folding a 128×128 grid on it. It's aligned on the bottom right corner with a full, virgin sheet (70×100cm):

It may seem negligible, 2.6% of shrinkage, but believe me - it does make a major change - squares are no longer squares, and a diagonal creases does not fall on the corners.

The right diagram shows how it should be done: in order to get the 38, pinch the 14 line and fold it upon the 12 line. To get the 2364 line, pinch the 22nd line upon the 24th line. And reverse that fold, so you will finish with all your horizontal creases as mountain folds.

The next tip regards the rotation of the paper. Since it is quite difficult to make a perpendicular crease against 64 mountain fold lines, do not crease 64 horizontal creases and then rotate the paper to complete the perpendicular ones. Instead divide a side in half, and rotate. Divide the new side into quarters, and rotate. Back to the first side, divided it into 8ths, and rotate. Divide into 16ths, and rotate. You get it, I hope.

The same logic applies to the Hexagon grid.

Some grids demand the diagonals to be folded, too. This brings up another tip - for grids up to 8×8, you can use the "fold the corner of a square to the opposite one" to fold line AB in one movement of the hand. For denser grids a more careful approach is needed. You can use the corner as a general guide, but when you mark the fold, refer to each single square as one - fold from the corner of it to the opposite one, and move to the next square. This is much tedious way, but far more accurate!

Precreasing

Unlike traditional origami, tessellations are mostly based on precreases. Some have a step by step way to get there, but for most you have to prepare all the folds in advance, and then collapse the model.

For most tessellations, this is the most time consuming phase. I think the most basic molecule needs at least 4 creases, and usually much more. Multiply your molecule number by that and understand how many short creases in all 4 directions you should fold. Luckily, there are short cuts for that. Many creases will align and can be folded in one stroke.

Notice that molecules 1, 2 and 3 in the image all contribute to one straight line (in red): the top-left fold line of molecule 2 (AB); the bottom-right line of molecule 1 (BC); and again the top-left fold line of molecule 3 (CD). So folding in one movement line AD gives you a major short cut.

Finding a shortcut is a bit harder with the inner squares that do not form a straight combined line. Here we move to another method: Counting. All 3 blue lines are aligned. Now start with the blue line of Molecule 1, and count 3 squares (marked in green) to get to the next square to which a diagonal fold needs to be added (in blue again). So this is the rhythm for that CP: crease 1, count 3, and repeat.

There is a cosmic law, saying that in every 32×32 grid and up tessellation you fold, you will make a mistake: dislocating a crease, jumping over a fold line in the grid, whatever. Do not feel bad. It's a cosmic law.

Collapse

Can't do it! Can't do it! Oh, maybe I can. (Deep breath). Oh, yes I can!

Yep, collapse is the stage that endangers your sanity. "It can't be done" comes to your mind again and again, and the cat jumps whenever a frustration cry is sounded. But, it really can be done. OK, enough with the psychology issues.

Collapsing a model can be done from center to edge, or from the corner, row by row. The rule is simple - with square grids I start at the corner, completing one molecule, folding the rest of the paper all the way to the edges, as if this is the only molecule to be folded. Then I add another one and so on, till the end of the row. The first row is simple. The second row starts easily, but the second molecule is surrounded from two sides with folded molecules and the other two sides are flat paper. This is where the difficulties lay. If you can fold that molecule, all the rest are just the same. For some tessellations, it is good to partially collapse all molecules in a row, before collapsing them one by one. This saves a bit of work in unfolding creases that will be in your way for the next row.

For a Hexagon tessellation, I always start from the center, (unless the center has no molecule, and then you start with the inner circle of 6 molecules). I do not really know why. This is how it is. Then you make the first circle around, with 6 molecules, when the last (the 6th in the first circle) can give you some troubles. This is mostly because you need to unfold some pleats you made to allow yourself to work on the paper. When opening the paper, you may have to be careful not to unfold the adjoining molecules - but it is necessary to complete that final molecule. If this proves too difficult, do try to fold the 5th and the 6th together instead!

The only tip I can give here is "do not give up". The folder is stronger than the paper.

When folding a tessellation, I sometimes found out that there is a rhythm, a repetitive method to do things correctly - write it down the moment you realize that sequence. It will help you tremendously the next time you try to fold it.

Tools

Paper

Elephant Hide.
Read Gadi's and my review to understand why: http://www.origamiusa.org/thefold001_paper
Tant
This is your second choice. The review was published earlier this issue.
Glassine
This is great for light effects.

Clips

"Egyptian Desert at Night" Tessellation designed and folded by Ilan Garibi, Elephant Hide

Do not start to fold tessellations if you have no clips, either metal or wood, and lots of them. The wood ones tend to break apart, and are too weak. You need to put 2 of them on every crease.

Some of the metal ones are too strong and leave their marks on the paper. But if your point of pressure is in the back of the model, (and do remember that a lot of tessellations are good from both sides) they are much better. You can also avoid the marks by using some padding (e.g. some extra paper).

Bone Folder

I use a professional Bone folder, from Nicolas Terry's online store (www.origami-shop.com) and thank god for that. My hands feel much better with that than folding with my fingers and fingernail pressure. North Americans can enjoy the Milk Jar Bone Folder - this redundant piece of plastic that hangs by the handle; parents for small children can use the flat, tiny scoop that comes with the Kinder eggs, to scoop the chocolate out.

Blu-Tack

During the precrease step, with many folds behind and more to come, you may become lost, losing your place and rhythm with the Grid. For that I have found a very useful method. Before precreasing, I mark the center of every molecule, or sometimes the first row and column only, with a Blu-Tack point. It can easily be removed without any residue, and will help you stay oriented throughout.

Plotter

Scoring is the procedure that weaken the paper where folds should be, in advance, either by hand or by machine (called Plotter). The masters even uses LASER plotters. If you are a mortal folder like me, you probably do not have one. So I do not score the paper in advance, but fold it traditionally. If you do want to give it a try, it can be done with a ruler and an empty ball pen (or any other blunt item you have). I have only one model that requires scoring. It's all made from curved lines, and I used an empty pen for that.

This topic could fill a few pages, but I do not have enough experience to do it. Maybe next time.

Bottom Line

One of my first original designs was actually a mistake I made on the day after one of our monthly meeting during the winter of 2008. Gila, a fellow folder, taught me how to puff seven stars on one sheet of paper. Trying unsuccessfully to reproduce this model at home I called her angrily, saying " I can not do it again! I got something totally different - I have the puffed stars with double the height and the distance from each other is too short!" . "Oh, great", she said, " you invented a new tessellation!"

Early 2011, a video about my Bricks Tess was made by Sara Adams, making me as proud as a father of a newly 4.7 Kg new born baby boy. I believe that by reading this manual and watching Sara's tutorial, you are well equipped to start some of your own mistakes! Good luck, and Happy Folding!