Flexagons are folded paper polygons that have the neat feature of changing faces as they are flexed. In this project, you'll make the tri-tetraflexagon, which is one of the simplest and easiest-to-make flexagons. It looks like a simple paper square with a front and a back, but hidden inside is another side (or face) that is revealed by folding the square in half and flexing it.
The name of a flexagon is special, because it tells the flexagon's shape and number of faces. For example, the name tri-tetraflexagon uses tri to indicate three faces, and tetra describes the shape of a four-sided polygon (square). In other flexagon craft projects, you can make a tri-hexaflexagon—a six-sided polygon (hexagon) with three faces (tri), or a hexa-hexaflexagon—a six-sided polygon (hexagon) with six faces (hexa).
Choose a tri-tetraflexagon to make. Download and print the pattern.
Choose a design that prints in color, or select one of the black & white patterns and use your creativity to add color and designs. It is easiest to fold patterns that have numbers or counting dots. Make one of these flexagons first before trying any of the others. To aid in folding and decorating the blank and unnumbered patterns, guides that number the faces are included on the patterns. The Labeled Guide pattern can be used to make your own flexagon creation from patterned paper or picture cutouts—see the Labeled Guide tip for more details. With the Half-Face Borders pattern, draw and color the faces after constructing the flexagon or use the face labels as guides for drawing each half of a face.
Patterns are Adobe PDF files. The Adobe Reader is available for free.
All of Aunt Annie's project patterns are designed to be printed on standard letter-size paper (8.5"x11" or A4). When printing from Adobe Reader, you may need to select Auto-Rotate and Center or Choose paper source by PDF page size to ensure the best fit.
Color the pattern template as you like with markers, colored pencils or crayons. You don't need to color the glue tabs marked with '*'. The Frames patterns are particularly suited to rubber stamp decorations.
Tip: On blank patterns, follow the Coloring Guide. All of the squares that make up a flexagon face have the same number, so color and decorate them with that in mind.
Cut around the pattern piece on the outline. Try to make the cuts very straight and accurate. The cutout pattern has 14 squares that, when doubled over and glued, result in seven squares.
Make a two-sided pattern with a double thickness by folding the pattern piece in half lengthwise and gluing. To make a sharp, straight fold, first score on the fold line.
To score: Use a ruler and the empty ballpoint pen (or bone folder) to make an indent along the fold lines.
Score and fold back and forth on all the solid lines. Do this for each of the seven squares of the tri-tetraflexagon. Follow the folding instructions very carefully.
Place the glued pattern as pictured, with the 3-3-1 sequence up and to your left.
Fold the leftmost square over the adjacent square on the line between the two squares numbered with a 3.
The squares with 3's are now on the inside of the fold, and the glue tab, *, is on top.
Fold back the three rightmost squares on the line between the squares numbered with 1 and 2.
The squares with the number 2 are now on the back, and the front side has three squares with 1s and a glue tab, *.
Pull forward the square marked with a 1 from behind the glue tab.
Now there are four squares of the same color, numbered 1, on the front, and four squares numbered 2 on the back.
The last step is to glue the flexagon. The two glue tabs marked with * are now face-to-face. Glue them together.
Wait for the glue to dry before flexing your flexagon.
With the side of the flexagon numbered 1 facing up, fold the flexagon in half vertically with the squares numbered 2 on the inside of the fold. Gently part the flexagon along the fold line to reveal the number 3 side. Now the number 2 side is hidden.
To see the number 2 side again, flip the flexagon over so the number 1 side is up, and repeat the flexing process. The tri-tetraflexagon is very simple, and has just two combinations of its three faces—sides 1 & 2 and sides 1 & 3. There is no way to get the combination 2 & 3.
That's it. Your flexagon is done!