This week Frances and I have been prepping supplies and creating a lesson plan for a design challenge at University Settlement. The challenge is to use patterns and fractions to create art. Since this design challenge will be the last one for the University Settlement campers, we decided to do a fun outdoor T-shirt making activity using bleach.
Each camper will receive a dark colored T-shirt with a large square taped off in the center. Their task is to create a fractal pattern out of masking tape within the square. A fractal is a never-ending geometric pattern that can be created by making a simple pattern and then repeating it on a smaller and smaller scale. An example would be to divide the square in half, then divide that half in half, repeating that process on each new half. Fractals are commonly found in nature as snowflakes, snail shells, plants, and lightening.
We will use an extract printing process with basic household bleach to make the patterns on the shirts. Bleach is a chemical that is commonly used to whiten or sterilize materials. Extract printing is a method of applying a design to dyed fabric by using a color-destroying agent, like bleach, to expose a white or lightened color on a the darker colored ground. In contrast, additive printing requires placing ink or paint on top of the ground. The difference between the two processes is that extract printing uses a chemical reaction to take away pigment, while additive printing uses a physical reaction to add ink or paint pigment.
We experimented with this process outside on a hot summer day. We set up a table, taped off our fractal designs, and placed various materials on the fabric to see what patterns were possible. We experimented with strings of beads, Popsicle sticks, toothpicks, stickers, pasta shells, and tape to reject the bleach with. The next step was to spray our pattern with a mixture of bleach and water. After sitting with the bleach for a minute or so, the fabric required a three-bath system to halt the chemical process. The first bath was just water to rinse the bleach, the second was a mix of water and metabisulfite, a chemical that neutralizes the bleach, and the third was a bath of water to rinse everything away.
This is a fun end-of-camp activity that is exciting to make and lets the campers take home their artwork to wear in the future!
At the end of our one week camp we introduce Tinkercad, a free online program, to introduce the students to 3D modeling. CAD software stands for Computer-Aided Design and is used by engineers, designers, and artists in the professional world. Tinkercad has an easy to use interface and is designed to teach 3D digital design for printing. Our lesson begins with getting the students to identify simple base shapes within complicated objects. Tinkercad has an index of basic shapes that are similar to the shapes we learn about for building inflatables.
After learning how to perform basic actions in the program, the students are free to start tinkering and creating objects. Students can break down the object they want to make into simpler shapes, like making a bed out of a rectangular cube and a pillow out of a half cylinder (or round roof as Tinkercad calls it). A piece of broccoli is formed with a base cylinder and a cluster of spheres on top. The possibilities are endless, and the students are free to be creative. However, it can still be quite difficult to think three dimensionally. A face that might seem perfectly aligned at one angle could, at a different angle, actually be floating shapes that are far apart from each other. Designing in Tinkercad requires awareness of space and the ability to constantly be rotating and viewing the design at all angles. Since we are viewing our 3D design on a 2D screen, it can be difficult to remember the space around, behind, above, and below the object. Despite the challenge, the students are able to push through and create complicated and well designed objects that can later be 3D printed.
On the last day of our 2D/3D camp we introduce our glue gun activity, which is an interpretation of manual 3D printing. Earlier in the week the students learned how to create shapes and objects using Tinkercad. We brought in our Makerbot 3D printer to show the class how the objects they are designing can be printed. As Leah wrote about last week, the Makerbot heats up a plastic filament until it becomes malleable enough to form the design layer by layer. The glue gun can be used in a similar fashion. The gun controls the extrusion of the liquid glue so that an object can be built out of glue using cross sections. In our class we use multiple fans so that the glue will dry quickly in order to be able to build up each layer. The Makerbot also uses a fan to make sure the plastic filament dries quickly enough for each layer of hot plastic to form on top of each other.
Each student receives a 3”x3” piece of clear acrylic, a low-temp glue gun, and four colored glue sticks. The goal is to slowly pour an outline of a shape onto the acrylic and with the help of the fans, build up the shape. Some students were very methodical, patiently waiting for each layer to dry, creating cubes and tall organic structures. Other students embraced the chaotic look of pouring the hot glue continuously in order to form a tower of scribbled glue. The objects created vary greatly, from volcanoes, nests, igloos, cats, a wizard, and simply abstract shapes.
At the office we explored this activity ourselves. Frances experimented using two planes of glue protrusion on her object. She built up a tree trunk and then turned it to its side and built up the branches at a different angle. If patient students are willing, we would like to push their boundaries and see if more students can build more complicated objects in future camps.
For our week long 2D/3D camp this summer, in the Cuyahoga County Libraries, we wrap up the week by showing the campers how to use Tinkercad. Tinkercad is a free online program where students can learn 3D modeling and build designs for 3D printing. During this part in our program, we also bring in a Makerbot 3D printer to demonstrate the process. On Thursdays and Fridays the campers get a run through on how to use Tinkercad so that they can design something to be printed on a Makerbot.
A Makerbot is a desktop 3D printer that we can easily take from our office to the the libraries. Once a students has made a design on Tinkercad, we save the design as an .stl file and open it up in the Makerbot software. The Makerbot software slices up your 3D model into cross sections that are a fraction of a millimeter in thickness. Since the material the Makerbot extrudes out is so thin it cools instantly and transforms the hot liquid plastic into a solid mass.
The filament used by the Makerbot we have for the camps is PLA plastic. PLA is made from starchy foodstuffs, is decomposable, and is also a thermoplastic. A thermoplastic is a material that becomes malleable above a certain temperature and once it cools down returns to a dense form. The filament is wrapped on a spool and has the thickness of a spaghetti noodle. This spool then attaches to the back of the Makerbot where it is fed through a tube that holds it in place as a motor feeds the filament through an extruder. The extruder is a small nozzle that melts the material. The Makerbot builds up material a fraction of a millimeter at a time. The machine extrudes plastic in cross sections determined by the Makerbot software.
At this camp we challenge campers to think about what 2D is, what 3D is, and how they can go from one to the other. By the time Thursday hits, the campers have made drawings, transformed those drawings into 3D models, taken those 3D models and broken them down into simple shapes to make inflatables. This way when they start working with Tinkercad they are already familiar with the shapes the program has and have a good grasp on how to use those shapes to create a design. The Makerbot is perfect to wrap up the camp because it shows the students how to draw in three dimensions on the computer and then how that drawing can be 3D printed in the real world. This activity lets them use their imagination in a practical way that shows them a new world of possibilities.
This week at University Settlement we challenged the group to create homopolar motors. Created in 1821, a homopolar motor is the simplest type of motor powered by electricity from a battery. The components of a homopolar motor are a AA battery, some disc magnets, and a long copper wire. The negative side of the battery is placed on top of the disc magnets and the copper wire is bent in such a way that it touches the positive side of the battery and the disc magnets simultaneously. This creates a direct current that powers a rotational movement, which we observe as the wire spinning around the battery. The students learned that homopolar means the same polarity. One magnetic field that does not change creates a Lorentz force. This is the force that is exerted by a magnetic field (disc magnets) on a moving electric charge (battery and wire).
The students had some frustration when trying to bend the wire in a way that would make it balance while spinning. Some students had trouble touching the wire to the top of the battery and to the magnets on the bottom, while at the same making sure the wire was a closed shape. The group was resilient though and pushed through the frustration and created kinetic sculptures by taping cut out magazine pictures and paper onto the wire. Through adding these paper objects we learned about weight distribution and balance when creating a moving object. The students were excited to see a static image became a moving object. One student utilized this by choosing a magazine cutout of a lion that also had a picture of a dolphin on the back. When it spun we saw both animals in rotation. Some students took a more comical route by taping pictures of local hero Lebron James onto the motor to watch him spin.
We learned about direct currents and how movement changes the quality of static images. The group had a lot of fun putting images in motion and tinkering with the motor so that it could balance and spin without interruption.