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TECHNIQUES

Why does my model look different from yours? My students have asked me this question many times. Part of the answer is experience and the other part is vision. The added skill obtained from experience is summed up in one word: technique.

Being an origami artist requires that you perfect many different skills, from folding to designing. As you gain more experience and develop your skills, your origami models will improve. As with any art, it is essential to learn the basics first. Without good folding skills, an artist cannot control the communication of his or her ideas. The clever technical skills that I developed prove useful when I create new origami art designs. When you look at a piece of origami art, ask yourself, “Is the designer’s message clear? Does the folder understand this creature or subject? How does the choice of paper complement the work? How has the execution of the folds, the choice of the model, the color and texture of the paper, its size and its overall appearance affected me?” You will soon see that it takes both technique and vision to make art. Once you develop your folding technique, you will be able to explore the art of origami.

A REVIEW OF THE BASICS

Before I discuss the advanced techniques used to create the projects in this book, it is important that you are well acquainted with basic folding techniques. Here is a quick review.

Folding Paper Neatly

The first and most important technique in origami is to move the paper correctly. So many people begin by folding a paper crane, only to be discouraged by sloppy points, a bent beak or white showing in the middle of the wings. Much of this can be resolved by taking care to place the paper properly before creasing the fold. Good eyesight helps, and forming the fold, then burnishing the creases with a bone folder tool or the back of a thumbnail, often makes all the difference. Generally, fold the paper away from you and crease the fold from the center to one side, then from the center to the other side. It is also important to place the crease exactly where it goes before burnishing it into place. Make sure you have good lighting and that you bend your head over the model to look straight down on the edges of the layers. Parallax will throw you off!

The process of folding a piece of paper begins with making a bend. As you decrease the radius of the curve of the bend, your commitment to the placement of the crease intensifies. You must check the position of the edges, making adjustments as you continue to flatten the bend. Some folds require that you focus on the placement of the crease, not the placement of the edges of the paper. For example, when folding steps 14 to 16 of the Cardinal, you should carefully decrease the radius of the bend while closely adjusting the roll of the flap until the crease intersects the exact corner of the paper.

Folding on a Table or Hard Surface

The best way to form a sharp crease is to burnish the fold with the back of your thumbnail against a hard surface, such as a table, board or hardcover book. Folding paper on a tablecloth will not work well. The use of a supporting surface is most useful where a clean, precise geometric look is desired. This is essential for paper airplanes and origami puzzles. A folding tool, such as a bone folder or the back of a spoon, is helpful where tough, heavy papers must be creased firmly, and to save wear and tear on your nails when folding numerous origami models.

Holding and Folding Paper in the Air

We often teach origami in schools and large assemblies, and so it is important for us to hold our paper up in the air so all can see each folding step. Invariably, we see students hold their paper in the air, too, so we tell them to use the table, and explain that we are holding the paper in the air to make it easier to see. Folding in the air is challenging to the beginner and we discourage it at these public events. When students are sure of their skills, however, they will find that folding off the table is essential to most intermediate techniques, such as inside and outside reverse folding and sinking, and advanced techniques, such as wet-folding. There is a dance-like choreography that is possible only when the paper is supported just by your hands.

Reading Origami Diagrams

Origami diagrams are easy to follow if you know the language. Mountain folds are indicated with dots between the dashes. Valley fold lines have only dashes. More complex maneuvers are often shown by several mountain and valley folds. The best clue is to look to the next drawing to see the resulting shape.

Basic Folds

Here is a quick review of the basic folds with which you should be familiar.

Edge to Crease

Most folds are created by lining up edges or placing an edge on a crease, then decreasing the bend until the two planes are flat. The beginner will often use visual signals to decide when the edge lines up. More advanced folders will align edges by feeling for the alignment. As you look carefully before placing the crease, be sure to bend your head over the alignment so that you can look straight across the two edges of the paper, perpendicular to the table. A folder who does this realizes that every sheet of paper has a thickness. Understanding and accounting for that third dimension is helpful when planning to eliminate gaps after reversing certain creases. Wet-folders using thicker papers tend to learn this quickly.

Inside Reverse Fold

When you pull a point between the outer layers of paper, you often turn a portion of a mountain fold into a valley fold. This maneuver is called the inside reverse fold.

Outside Reverse Fold

When you pull paper back over itself to enclose the other two layers of paper, you also turn the tip of the paper over, showing the other side. This maneuver is called the outside reverse fold.

Rabbit Ear

When you pull in paper from two directions and are left with excess that sticks up in the middle, the maneuver is called a rabbit ear.

Squash Fold

When you raise a multilayered flap perpendicular to the table and the remaining paper, open the layers, then press the center mountain fold flat to the table, this is called a squash fold.

Petal Fold

When you pull a point across the other layers of paper, lengthening the form by bringing in paper from the sides to cover the top, you are making a petal fold.

Sink

When you reverse the mountains and valleys that form a point or peak in order to create an indented form, this maneuver is called a sink.

Crimp

When you grasp a folded piece of paper and insert a symmetrical, mirror-image pair of mountain and valley folds on either side of the central mountain fold, the central mountain fold turns direction due to a maneuver called a crimp.

ADVANCED FOLDS

The advanced folding techniques used for the projects in this book include curved folds and wet-folding. These techniques take time to master, but they are crucial to creating complex models.

Curved Folds

Folds do not have to follow straight lines. Sure, straight folds are easy. Since two points define a line, two landmarks on an origami model often describe a great place to make a fold. Why make a curved fold? There are two reasons: one part is technological, the other is aesthetic. A curved fold locks its own shape. A straight fold is nothing more than the spine of a book, where pages are free to open and close about the spine line. A curved fold is a tension-compression structure, one with give and take. It demands that the paper respond elsewhere. A curve yields a softer appearance and throws a softer shadow. For these reasons, wet-folders often finish their models with a series of curved folds, a process that can take much longer than all of the straight folds leading up to the finishing steps.

To make curved folds, trace an arch with your thumb and index finger in the paper. Use these fingers in concert to “draw” the shape of the curve you need. Curves may be gentle or sharp; they may be sinusoidal. Curved creases can add dimensionality and a lyrical, animated quality to the sculpture.

Wet-Folding

Wet-folding allows the paper to keep its integrity since the fibers will bend and not break as they do in dry folding. Moreover, the models stay folded after they dry. Heavy papers that could otherwise not be used can be wet-folded because they become flexible and compressible once they are wet.

Wet-folding changes everything. The paper fibers swell, often in one direction more than the other (see the Grain section on page 19). This throws off the point-matchers—dry folders who align every crease by matching points. The wet-folder locates the crease, not the points; there is a difference. The advent of wet-folding brought about a new style of origami art. Wet-folded origami fish now appear to be swimming thanks to the graceful curves possible in the fins and other folds. Wet-folded origami flowers seem to be growing, and butterflies no longer look like pin-mounted specimens in a museum box.

Ever since I began folding my own handmade papers and other soft Asian papers, I realized that I needed to back-coat or add size to them to make them stiffer. I had learned about cooking starch paste for other art projects, but since my family was in the construction business I had methylcellulose wallpaper paste readily available. It did not require cooking and when it dried it was invisible. I tried it. Methylcellulose proved ideal for my origami art. When I folded my orchid for the first time, in 1973, I was experimenting with machine-made crepe paper. I realized that I needed to add both water to fold it and size to keep it in shape after it dried. Instead of moistening and surfacesizing the entire piece of crepe paper (which would have destroyed the creping), I dry-folded the model but applied methylcellulose strategically to stiffen the lip and petals and to hold other layers together as I folded it. Since then, I have referred to this method as “folding with live paste” and I use it for folding insects and other complex designs that use very thin papers requiring additional stiffness.

Soft, rounded, gentle curves and expressive sculptural folds characterize many of today’s excellent wet-folded models. Wet-folding requires paper with supple, long, strong fibers. Wet-folding enables the fibers to be bent, not broken, upon folding. This allows the artist to tackle complex designs that often require multiple folds along the same line or intersecting at the same point. Dry-folding these complex models would not be possible without breaking through the paper at key intersections. After being wet-folded, the subsequently dried model will retain its shape, a property particularly cherished by the serious origami art collector. Wet-folding will allow you to make use of a greater range of art papers that would be too thick to fold dry.

Typical papers chosen for wet-folding are often heavier and rather soft. You should rarely burnish wet paper with the back of your thumbnail since wet paper is prone to bruising. When wet-folding large paper in the air, you must use gravity to its best advantage, folding downward from the top, letting the hanging portions of the paper guide your fingers to their target.

Wetting the paper with water can be done in several ways, but the water must always be added to both sides of the sheet to mitigate curling of the paper. Water may be sprayed with a plant mister. You can also apply the water with a damp cloth or sponge.

Be sure to apply water evenly across the sheet and allow the water to be completely absorbed into the paper. Use the least amount of water possible. The paper should be limp and cool to the touch but it should not look wet! Add more water as needed while folding. A small, soft paint brush or the corner of a rag is useful for this purpose.

Every project in this book can be wet-folded but some, such as the North American Cardinal (page 28) and the Origamido Butterfly (page 33), will require relatively little moisture, and often that need be applied only along the line of an important crease.

Preparing Your Paper for Wet-Folding

The surface properties you want for your paper will be dictated by the characteristics of the model. A leathery creature, such as a bat, requires a stiffer fiber and plenty of sizing. A fuzzy subject, such as a piglet, requires softer fiber, such as cotton, with its fuzzier texture and warmth. Folding can be tough on the surface of the paper and most wet-folders prefer to use a size/lubricant/ paste. When it is wet, it is slippery and protective. When it dries, it seems to vanish completely. The most popular mediums used are wheat paste or methylcellulose.

Starch Paste

Archival starch paste can be made from corn starch, potato starch or wheat starch. Begin by boiling water in the lower chamber of a double boiler. Add cold water to the upper chamber, measuring five times as much water as starch (volume to volume). Add all the starch to the water and use a whisk to mix the milky suspension. Continue heating and mixing the suspension for about 20 minutes. As the starch cooks, it thickens like pudding and begins to clear. When it cools, it thickens further.

Some artisans develop a ritualistic approach to preparing wheat starch. It is a food source for some creatures, so if you are not careful with the purity of the water, the percentage of starch, the temperature or other factors, microbial growth can turn starch into sugar.Allow it to ferment and the mixture can become even further contaminated. Acidic impurities are almost always harmful to the qualities of the paper. For these reasons, we prefer to use food-grade methylcellulose.

Methylcellulose is a readily available shortcut to the traditional wheat paste used by Yoshizawa and other paper artists. It is refined and pure, so the extensive aging and purification steps are unnecessary. Most paint and wallpaper shops carry dried methylcellulose. Hand papermaking, book-binding and library arts supply companies also carry methylcellulose powder.

Methylcellulose: Preparing 10 Percent Methylcellulose in Solution (by volume)

We often prepare a batch of methylcellulose by gently adding 2 ounces of methylcellulose powder (using a liquid measuring spoon), to 20 ounces of water (using a liquid measure). Sprinkle the powder slowly onto the surface of the water as you mix the water and the methylcellulose with a stirring spatula, using a brisk mixing action. Be sure to scrape down the edges to keep the expanding polymer wet. The process is faster if you use a blender although it does tend to entrap more air bubbles.

Using either method, allow the solution to sit for at least a day or two to let the lumps of polymer dissolve. Artist-quality methylcellulose seems to be a bit easier to work with than the kind sold in wallpaper stores. This mixture of viscous material has a slippery feel, just a bit lighter than honey. (Be careful not to spill this on the floor since it is extremely slippery.)

Internal size is key for some origami models. We are not too fussy about internal size any more since it is easy to add size just before wet-folding begins. It is more versatile to leave the size out until you are sure of what you need.

Applying Size to Paper

Wet-folding is often easier when the sheet is conditioned with a lubricant/size, such as methylcellulose. Before you wet the paper, cut it perfectly square. Adding moisture swells the fibers. After the model dries, the paper will return to its original dimensions.

1. Materials needed for adding surface size to paper: spray mister, methylcellulose powder, wide brush, bowl, paper.

2. Moisten the paper with water, front and back, using the finest spray setting on a spray mister. Gently spread the droplets with a light sweep of a wide, fine-bristled brush (sometimes we use a sponge or a damp cloth). Be sure not to abrade the paper when it is wet. Allow enough time for the moisture to migrate throughout the paper.

3. Brush the 10 percent methylcellulose gel onto the paper. Spread evenly from the center to the edges. The methylcellulose will penetrate the paper and adhere to the glass or plastic below.

4. Allow the preparation to dry completely. One coat is usually sufficient but allow each coat to dry if additional coats are desired.

5. Peel off the sized paper. The paper will be ready to fold when it feels like leather.

Back-Coating Two Sheets Together

When you find a nice piece of paper that is too lightweight or soft for wet-folding, back it with stiffer or stronger paper. We use methylcellulose or wheat paste to bond the two sheets back to back. Follow these steps to back-coat two sheets of paper together. This is also how we make two-color (duo) models.

1. To back-coat two sheets together, you will need the tools shown here: starch or methylcellulose powder; bowl and wet brush for the prepared paste; spray mister; wide, dry brush for smoothing; a knife (not shown). You can use a large plywood board, foam core or stiff plastic to support the back-coated sheet as it dries.

2. To begin, cut the backing paper about an inch larger than the delicate paper. Moisten each side of each sheet with a fine mist of water. Make sure they have expanded fully. Decide which side of the papers you want to show.

3. Smooth the water droplets with a wide, soft brush, working from the center to the edges. Coat the backing paper evenly with methylcellulose or paste in the same way, brushing from the center to the edges.

4. Using a wide, soft, dry brush, apply the second sheet onto the glue layer. Note the use of a wooden slat to control the upper free edge of the back paper as it is being lowered. Use a second wide, soft, dry brush to brush away any air pockets, working from the center to the edge. Be sure not to get paste on the brush!

5. After the air bubbles are brushed out, use the first paste brush to carefully apply another layer of paste to the exposed margin of the backing paper (this is showing beyond the edges of the nice paper).

6. Lay a small strip of paper across the glued margin to form a “gate” or “mouth.” This mouth provides a knife-insertion point that will speed up the removal of the dried sheet from the drying board.

7. Turn the wet composite over onto the surface of a board for drying. Use a clean, dry, wide brush (or the dry brush you previously used) to smooth out any air pockets and ensure good contact at the margins of the wet assembly.

8. After the composite is dry, carefully insert a sharp knife between the drying board and the paper at the mouth. Slide the knife around the margin to release it from the drying board.

9. The dried “duo” paper is now ready for trimming and wet-folding.