How to Open a Folded Wing and Squash the Section Inside

A squash fold opens the layers of a flap and spreads them into a flattened shape. In Make-Origami’s basic example, one flap is raised upright, its two layers are eased apart, and the paper is pressed down evenly. The flap changes shape while remaining attached to the surrounding model. Make-Origami: Squash Fold

For a folded wing, treat the instruction as two separate actions. First, move the wing into the position shown. Then identify and flatten the section exposed within it. This separation is a practical way to interpret the instruction; it does not establish which particular pocket your model uses.

Do not assume that “inside” tells you to tuck the wingtip into the body. Tuttle’s folding instructions distinguish a squash fold from an inside-reverse fold, describing the latter as bringing a point inside a layer. Check the named movement and its diagram before changing the paper’s direction. Tuttle Publishing’s Frog instructions

Place the model beside the current diagram and look ahead to the next completed view. Compare three references: the wingtip, the wing’s attachment to the body, and the edges surrounding the section you will open. Use these as checkpoints throughout the move.

Looking ahead is especially useful when the paper must pass through a three-dimensional position. In Michael LaFosse’s Alice Gray Butterfly instructions, the publisher explicitly directs the folder to subsequent views for the shape and shows squash folds in progress. A partly opened pocket is an intermediate position, so it need not resemble the finished silhouette yet. Tuttle Publishing’s Alice Gray Butterfly instructions

Before proceeding, answer these questions:

• Which flap does the arrow indicate?
• Which existing crease lets that flap move?
• Where should its point or folded edge finish?
• Does the next view show the same side of the model?

If an answer is unclear, return to the preceding completed view and compare the layer arrangement. Avoid choosing a pocket solely because it is the easiest one to reach.

Support the body on the work surface and lift the indicated wing enough to see its layers. For the standard squash-fold setup, the flap can stand approximately perpendicular to the model while its layers separate. Make-Origami demonstrates this upright starting position in its preliminary-base example. Make-Origami’s illustrated method

Work through the opening in small stages:

1. Move the wing along the hinge shown in your instructions.
2. Pause with the inner section visible.
3. Locate the opening between the indicated layers.
4. Ease those layers apart with your fingertips.
5. Leave the pocket open while you identify its alignment reference.

At this stage, use a simple checkpoint: can you still identify the wingtip and body attachment you selected earlier? If either has disappeared beneath an unexpected layer, pause and compare the diagram again. This check helps separate an orientation problem from a flattening problem.

Once the correct pocket is open, lower its raised folded edge toward the position shown in the completed diagram. Allow the sides to spread as the pocket flattens. In the standard method, the crease on the upper layer is aligned with the underlying paper before the squash is completed. Origami Resource Center’s basic squash-fold method

Use three deliberate passes:

1. Position: bring the raised section close to its destination without sharpening the new folds.
2. Compare: check the point, center crease, and outside edges against the next diagram.
3. Finish: hold the alignment and press the section flat.

For an ordinary symmetrical practice squash, check that both sides contain equal amounts of paper. Make-Origami identifies evenness and crease alignment as features of a well-formed basic squash. Apply symmetry only where your model calls for it; an angled wing section must follow its own diagram. Make-Origami’s alignment guidance

Do not add an arbitrary fold merely to make the pocket stay down. If the result requires a new crease location, that location should come from the model’s instructions. Keep the collapse lightly formed until its outline agrees with the intended result.

If your instructions already specify a fold-and-unfold step, inspect that crease before trying the squash again. Origami Resource Center presents a precreased alternative: fold and unfold the flap, lift it, open the layers, and flatten it. In that example, a valley crease changes to a mountain crease during the movement. Origami Resource Center’s alternative method

This means an existing crease may need to change direction. It does not mean every visible crease should reverse. Follow the particular fold lines in your diagram, and reinforce only the references that belong to the current step.

Tuttle’s frog sequence provides a useful example of preparation: the outer folded edge is brought to the center before the next instruction calls for a squash fold. That sequence illustrates why an earlier alignment step can matter to a later collapse. Tuttle Publishing’s Frog instructions, steps 4–6

Use the following sequence as a diagnostic aid derived from the opening and alignment methods above. These are checks to try, not certain explanations for every model.

What you see	What to check next
The wing moves, but no pocket appears	Confirm that you have lifted the indicated flap and separated its intended layers.
The body moves along with the wing	Compare the hinge and layer selection with the previous diagram.
The pocket opens, but its point lands off target	Reopen the light collapse and check the crease reference before pressing again.
The section forms an unexpected pleat	Check whether a layer remains caught inside the opening.
The fold lies flat but the outline looks wrong	Compare orientation, visible layers, and the next completed view.

Change one thing at a time. For example, reopen the section, confirm the active layers, and then retry the alignment. Making several new folds at once removes the useful distinction between the original creases and your attempted corrections.

Check the result against the model’s next completed view: the wing should occupy the intended position, the squashed section should have the shown outline, and the visible edges should appear in the correct order. If the instructions call for repetition, complete and inspect one side before starting the other. LaFosse’s butterfly instructions likewise specify forming the wing squash folds one at a time. Tuttle Publishing’s Alice Gray Butterfly instructions

Finish by checking the same three references you started with: wingtip, attachment, and inner section. When all three match the diagram, sharpen the folds and continue. Keeping opening, alignment, and firm creasing as separate actions makes this compact instruction easier to carry out accurately.

• Origami Squash Fold — Origami Resource Center
• Squash Fold — Make-Origami.com
• Frog — Tuttle Publishing folding instructions (PDF)
• Alice Gray Butterfly — Tuttle Publishing folding instructions (PDF)