Introduction: Curling Spiral Kinetic Sculpture
This instructable is inspired by mathematician and artist John Edmark's fascinating work in kinetic sculptures, transformable objects, and the surprising structures hidden within the geometry of nature. As soon as I saw his curling spirals, I knew I had to figure out how to make one for myself. The way the sculpture curls so naturally when you fold the sides open is so mesmerizing and lifelike. In the future, I think it would be really cool to make this interactive object into more than just a wooden frame-- a geometric octopus tentacle maybe?
Step 1: Materials
Glue (I used both hot glue and white craft glue)
Non-stretchy fabric (for joining the wooden pieces together)
Step 2: Download Files
I've included an Adobe Illustrator AI vector file and a PDF file that you can use with your laser cutter.
The design has 2 symmetrical sides, each side made up of 18 wood pieces that are joined together to form a geometric spiral. Each of the 18 pieces are the same irregular quadrilateral shape but different sizes. The pieces line up perfectly so that between any two consecutive pieces, the shorter side of the larger piece is the same length of the longer side of the shorter piece.
Step 3: Laser Cut
I used a Universal Systems laser cutter to laser cut the design out of 1/8" plywood.
Since there's so many pieces, and the order in which you glue them together is very important, I suggest stacking them together in order of size so that you can keep track of them easily. I made 2 stacks: 1 stack for each side of the spiral, and 18 pieces in each stack. The included design file is organized so that you can easily see the order of the pieces.
Step 4: Assemble the Two Sides of the Spiral
Now it's time to join the pieces together using glue and strips of fabric.
With fabric scissors, cut the fabric into strips that are 1/2 inch thick. You're going to need strips that are just long enough to fit between each pair of pieces. Each piece will have a fabric joint on three of its sides, except for the four pieces that will be at the very ends of the spiral.
I tried two types of glue: white craft glue and hot glue. The brand of white craft glue that I used was Tacky glue. After trying both methods, I found that hot glue was a lot easier and less time consuming than white craft glue. However, I would only use hot glue if you have a high heat glue gun, so that the glue stays melted long enough to give you time to set up the fabric joint. With a low temperature glue gun, the glue cools off and hardens too fast. If you don't have a high heat glue gun, just use white craft glue.
The pieces line up perfectly so that between any two consecutive pieces, the shorter side of the larger piece is the same length of the longer side of the shorter piece. Spread an even layer of glue on the fabric strip, between two wooden pieces, and press firmly until dry. Do this for all 18 pieces. When you are done with one side of the spiral, then assemble the other side in the same fashion, except this time the spiral should curl in the opposite direction. Notice how in the sixth picture, there are two spirals that are facing the opposite direction from each other. We want to sandwich both spirals together and join them together on the outer spine, so that the fabric joints are facing each other inside.
Step 5: Glue the Two Sides Together
Now comes the tricky part: joining the two spirals together along the outer spine. Cut more 1/2 inch thick fabric strips. Take one spiral and glue the fabric strips along the outer spine, so that half of the strip is connected to the spiral, and the other half is hanging off, as in the first picture. Take the other spiral and place it on top of the first spiral, with fabric joints facing each other inside, so that they both line up nicely and form the two sides of the sculpture. Then fold in half of the fabric strip that you glued along the outer spine, add some glue on top of the flap of fabric, and press the other spiral on top so that they are hinged together. Repeat this for each of the 18 pairs of wooden pieces, until the whole spiral is joined.
Step 6: Viola! You're Done!
To curl and uncurl the spiral, simply one hand on each side of the spiral at the base (the largest piece at the end of the spiral) and move your hands toward and away from each other (like opening and closing a book). When your hands move closer together to close the gap between the two sides of the spiral, the spiral will uncurl. Moving your hands farther apart will make the spiral curl up into a ball.