Designer: David Brill
Text-Based Instructions copyright 2025 by Lindy van der Merwe and Annette Carr
Access Origami
For basic instructions with visuals, visit
Origami Resource Centeror see the following video by
The Smart Happy Project
Description
This model is a dodecahedron, meaning it is a solid shape with 12 pentagonal faces. It makes a nice decoration and is often used as a base for calendars.
It can be an interesting and practical classroom project, suitable for various learning levels and areas.
Since it is a hollow geometric shape, it can also hide a surprise, but of course it will fall apart when opened, so only use it for this purpose if you don't mind this happening.
Steps: 25
Folding level: Intermediate
Paper to be used: 12 silver rectangles or sheets of A-sized paper, like A4, A5 or A6, plus 1 or 2 rectangles to use as templates.
If you live in a country where A-sized paper is readily available, you can fold your A4 sheet in half with short sides together. Cut or tear along the crease to make 2 A5 sheets. Similarly, you can fold an A5 sheet in half by bringing the short sides together. Cutting along the center crease will produce two A6 sheets.
If you do not have A-sized sheets, the sizes of the three sheets in question are as follows:
A4 paper size is 21.0 cm by 29.7 cm.
A5 paper size is 14.8 cm by 21.0 cm.
A6 paper size is 10.5 cm by 14.8 cm.
A4 paper makes a really large dodecahedron, so you might prefer to try out A5 or A6 paper first.
You could also try a quarter sheet of 8.5 by 11 inch (21.5 by 27.9 cm) printer paper.
This will make a model that will be around 4 inches (10 cm) in diameter.
Please read the tutorial in full before starting to fold units, making sure to read Notes 1 and 2 pertaining to folding the first and/or second units as templates.
Also note that, in Phase 4 of this tutorial, you have a choice of two assembly methods for this geometric model, marked as Method A or Method B.
Instructions
Phase 1 - Creating a unit
Step 1
Place your rectangular sheet in portrait orientation, with the long edges on the left and right.
Important: Make sure that you do not change the orientation of your sheet until the folding of your unit is complete. Even though you will be folding at different angles, the creases you will make in Steps 2 and 3 should stay vertical and horizontal, respectively.
This will make things much easier as you add more folds to the unit.
Step 2
Fold in half from top to bottom. Crease and unfold.
Step 3
Fold in half vertically, but only make a short crease mark at the center or, if you don't mind a crease on the outside of your unit, you can make a full vertical crease.
We will use the center point, where these two creases intersect for the next steps.
Step 4
Turn your sheet over from left to right, like turning the page of a book.
The mountain creases that you will now have to work with will be more prominent and easier to feel than valley creases.
Step 5
We are now going to fold the four corners of our rectangle, one at a time, inwards to meet the center point we have just created.
You might find these folds difficult to do accurately at first. Even a small deviation by any of the folds from the center mark will cause your unit to end up lopsided. It is best to fold the points in one at a time since then you will not have other points obscuring the center of the paper. If the lines seem faint, re-crease them so that your center point where the lines cross can be felt clearly.
5.1
Starting with the top left corner, fold it diagonally to meet the center point just mentioned.
Try to be as accurate as possible. Crease and unfold.
5.2
Fold the bottom right corner into the center in the same way. Crease well and then unfold.
5.3
Repeat the previous two steps, but this time with the top right corner and the bottom left corner, each time creasing and then unfolding.
5.4
Once you have made the four creases, fold two opposite corners into the center first, leaving them folded and then adding the remaining two opposite corners. It does not matter which corners you fold in first as long as they are opposites.
Result: The folds will overlap and form a flat figure that can be described as an irregular hexagon or six-sided shape.
You will have the opportunity to check the accuracy of the four folds from this step once you have completed the following step.
Note that your flat unit will have two areas with the raw edges of the paper still showing. One will be on the left and the other on the right. Nearest you and also pointing away from you, there will be diagonal edges that slope into fairly sharp points.
Step 6
Using the original horizontal crease you created in Step 2, fold the figure in half by bringing the bottom sharp point up to meet the top sharp point.
Make sure that you have placed the bottom point exactly on top of the top point.
Investigate your folded shape. It should be five-sided with a long hinge fold nearest you, two short edges at the bottom left and right sides and then two long diagonal edges that slope upwards to meet at the top point of the figure.
If the long sloping sides differ markedly, you might have to refold the four folds from Step 5, since you would like for the back and front of the pentagon to match exactly if you trace the outer edges of the shape.
Note 1:
It is a good idea to measure your units against each other or keep this first unit as a template, to make sure you are folding units with similar angles and of the same size throughout.
Step 7
Now, take the top sharp point of the unit, the top layer only, and fold it down, using a mountain fold, to meet the inside center of the bottom edge.
Make a strong horizontal crease and then unfold.
Step 8
Ensure that you can also feel the vertical crease mark or line from Step 3.
Step 9
Next, we have to fold the short left and right bottom edges of the unit in towards the center. This will not only make our pentagon a more regular or balanced shape, but it will also create two tabs or flaps that will be used to assemble our dodecahedron.
In general, the two short edges will be folded inwards and upwards at an equal amount and at the same angle, both reaching and overlapping each other slightly across the vertical and horizontal center of the pentagon.
What we are aiming for is to create three sides at the bottom of the pentagon that will be the same length as the two sloping sides that are already forming the top corner of the figure.
In other words, we would like for all five sides of the pentagon to be the same length.
To help us with the two folds, we will use the vertical and horizontal crease lines of our figure.
9.1
Think of the short left edge of the unit as an arm, which we will be folding upwards and inwards, so it will reach the upper right area of the figure.
Notice that the short edge we want to fold itself has a top and a bottom point or corners.
First, however, we have to pinpoint the angle and the distance of this fold. So, place a finger at the center of the shape. Move one finger upwards and another to the right, perhaps a cm or 2, depending on the size of your starting sheet. These two imaginary points are where your left folded short edge should land. So, the top corner of this edge will meet the point you have identified along the vertical center crease, while the bottom point of the short edge should meet the point you have identified along the horizontal edge.
The top corner of this fold should be in line with the top corners of the entire shape as well.
Do your best estimation and make a strong crease along the left side of your unit and leave folded for now.
9.2
In a similar way, pinpoint two marks a small distance from the center point of the shape. This time the arm will be folded to reach the left, upper area of the figure. Try to fold the right arm at a similar angle to the left. The top point of this arm will come to rest exactly on top of the top point of the arm that has already been folded from the left.
Make a strong crease on the right side of the figure and unfold both arms to stand at a 90 degree angle in relation to the table.
Note 2:
To check the accuracy of these last two folds, you can gently bend the left side of the unit over to meet the right side. The four edges that will now meet should all be of a similar length. Once you are happy that your unit has a regular or balanced pentagonal shape, you can once again use it as a template to measure the rest of your units.
Step 10
Next, open the shape just slightly and locate two vertical flaps on the inside, near the top center point of the shape. Use both hands to gently twist the flaps so they will overlap each other on the inside of the figure, locking the front and back of the unit together.
This action will not only keep the unit neatly closed, but it also creates two separate pockets along the top sloping sides of the figure.
Phase 2 - Fold More Units
Step 11
Fold 11 more pentagonal units.
Step 12
Explanation
Since you will be rotating the units in various ways during the assembly that follows, make sure you can identify the following parts of each unit:
a flat, central area with a closed hinge, two flaps or arms across from each other and two pockets, adjacent to each other.
Ensure that the arms of all units are unfolded halfway. They should stand at around a 90 degree angle in relation to the main pentagonal body of each unit.
Phase 3 - Creating a 3 Unit Module
Step 13
Place your first unit flat on the table with the closed hinge nearest you. The flaps will be on the left and right, pointing upwards to the ceiling and the pockets will be accessible from the side furthest away from you.
Step 14
Pick up unit 2 and hold it up in front of you like a book. Orient it so its hinged edge is on the left. The two flaps will be sticking out towards you, with the pointy end on the right.
Step 15
Find the right pocket of unit 1 and insert the flap of unit 2, that is nearest the table, into it.
Unit 1 will lie flat on the table, while unit 2 will be standing up, like a wall, slightly to the right of unit 1.
If necessary, anchor the first two units with a finger while inserting unit 3.
Step 16
Take a third unit and hold it so that the hinged edge is nearest the ceiling. The two flaps should be pointing towards the left and the two pockets of the unit will face the table.
Step 17
Locate the right pocket of unit 2, which will be closest to the table. Press the right flap of unit 1 flat so it is out of your way for now.
Step 18
Insert the flap of unit 3 into the right pocket of unit 2, approaching from the right at an angle.
Unit 3 will slide into the side of unit 2 and will also stand upright, like unit 2.
Step 19
Lastly, you will join the right flap of unit 1 into the nearest pocket of unit 3. So, lift up the flap you have pressed flat in a previous step and also lift up unit 3 just slightly. The flap will slide into the pocket, securing unit 3 so it will stay upright.
You have now assembled three units, forming a kind of corner of your dodecahedron.
Phase 4 - Two Methods of Assembly
Method A
Step 20
Repeat Steps 13 to 19 three more times, forming three more "corners" of your geometric shape.
Step 21
Arrange your assembled pieces on a table as if they will be forming the four corners of an imaginary square block.
Each piece will have one unit flat on the table with two units standing up around it.
Step 22
First connect two of the combined shapes by turning them slightly towards each other and then linking them sideways, sliding flaps into pockets.
Remember that there will be no join where the hinged edges of two units meet. The units will simply press against each other and be held in place by the rest of the assembly.
Move the shape you have just formed to the side for now.
Step 23
As you did before, turn the two remaining units slightly towards each other and connect them by inserting flaps into pockets.
You should end up with two identical assemblies, each made up of six units.
Step 24
Now, place the two assemblies so they face each other, one should be on the left and one on the right. Move them so the units are almost touching and work on the side nearest you to join the left and right sides. Turn the assembly carefully so that the opposite side is now nearest you, allowing you to join the last units into the final, closed shape of the dodecahedron.
Step 25
Gently press all the units together with the palms of your hand if necessary and marvel at the symmetry and beauty of this remarkable geometric shape.
Method B
Step 20
Examine your 3-unit module. It has 3 flat pentagon faces; 3 connected edges; 1 complete corner where the 3 joined edges come together; and 9 edges that are made up of arms/flaps, pockets, and hinged edges. As you examine the 9 edges of the perimeter of the 3-unit module in a clockwise direction you will find a repeating pattern of an arm/flap, a pocket, and a hinged edge.
Step 21
Position 2 3-unit modules in front of you as follows:
21.1
Position the first module on the left so that one pentagon is on the table with an arm/flap on the right and a pocket on the edge closest to you. There will be a second pentagon standing up from the lower left edge, and a third standing up from the upper left edge of the pentagon on the table. Pentagons 2 and 3 are connected.
21.2
Position a second 3-unit module to the right of the first. It will have 1 pentagon on the table positioned with an arm/flap towards you and a pocket on the left. Pentagons 2 and 3 will be standing up opposite you.
Step 22
Working with the pentagons that are flat on the table, insert the arm/flap from the left pentagon into the pocket of the right pentagon.
Step 23
In front of the connection you made in the previous step, you will find 2 hinged edges and then a pocket on the left and an arm/flap on the right. Insert the right arm/flap into the left pocket.
Step 24
You now have 6 units assembled. The remaining 6 units will be assembled one at a time based on the following rules
24.1
The arms/flaps of a pentagon will always be pointing towards the inside of the structure as you are positioning the unit to add it to the model.
24.2
Hinged edges will always be lined up with hinged edges.
24.3
When there are 2 arms/flaps right next to each other, they will be inserted into the 2 pockets of a single pentagon.
24.4
After attaching a unit, check to see if it has a pocket or arm/flap that is lining up with another pentagon. If so, make the connection.
Step 25
Once all 12 units have been assembled, examine the model to make sure all of the connections between pentagons have been made. Sometimes arms/flaps end up inside the model and are not inserted into a pocket. You should only be able to stick your finger inside the model where 2 hinged edges meet.
Making origami accessible through text-based instructions.
For non-commercial use only.
Compiled by Lindy van der Merwe and Annette Carr, May 2025
This text copyright 2025 by accessorigami.com
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