The first thing I made is a simple rectangular piece with an LED embedded inside. I used conductive tape for the two ends of the LED and cast it inside the silicone. Here, I used one drop of the purple dye to get a great violet for the silicone.

The results of this experiment works quite well.  The effect of the LED shining through the translucent  layer of purple silicone is very pretty. From this initial experiment, I learned that the silicone is very messy to work with, but it spreads evenly by itself quite well.

Then, I started to explore the possibility of integrating thermo chromatic paint into the silicone piece and see how it would behave. I found some dried thermo chromatic paint (aqua) in the lab and crushed it into chunks. I left it as chunks and mixed into part B of the silicone. I wanted to see the behavior of the color change of chunks vs specs of the thermo chromo paint.

I put conductive thread across different parts of the casting hoping to see the color change when I put current across the wires. The results turned out to be quite stunning. Silicone turns out to be a great insulator. It takes about 1.5amps to change the color dramatically. To see a quicker color change, I used a heat gun, and that’s the most dramatic change. I was specifically interested in the chunks vs specs and how they change color. The result was that the chunks changed colors faster than the specs. So, when I blow a heat gun across the cast, the chunks turn color faster than the other, less concentrated parts.

Next, I tried out the effects of fiber optics and its ability to direct light within double layered silicone casting. I found some fiber optic wires lying around and chopped them into small pieces with a wire cutter.

I had planned to lay them out so that they are orthogonal to the surface. However, this task was very difficult to do because it was very hard to place tiny pieces into a certain configuration, especially when the second layer of silicone was added to the mold on top of the tiny pieces.

Lastly, I put three drops of paint of  different colors onto the top of the silicone, and make swirl patterns. The intention of this is to be able to see the different colors as light is directed to the end of the fibers. It wasn’t a good idea to put dye on top of the silicone because after the silicone cures, the dye is not stable enough to maintain its form. Therefore, it rubs off on heated contact.

After the first few experiments, I gained enough experience with the silicone to begin doing more with it.  I am very interested in making stretch sensors with the silicone. My vision for such a device is one whose resistance decreases when stretched and lights up the an LED to make the visual signal of change in resistance.

For my first iteration, I use latex with carbon fiber and 4 LEDs. The latex cures more quickly than the silicone so I chose it as a “first try.” In order for this sensor to work, I realized that I need to use a lot of carbon fiber so that the fibers will touch even if the material is stretched.

This sensor works, but it doesn’t work very well. When it is not stretched, it has very little resistance (around 1k ohms) and when it is stretched, the numbers jump around the vicinity of 1M ohms. However, it seems that once the material is stretched, it doesn’t spring back to its original form. This makes the sensor unreliable and hard to work with.

The second iteration is using silicone with schoeller wool and LEDs. The appearance of the casting turns out to be much better than the one made with latex, mostly because silicone cures clear, not yellow. I layed out the schoeller wool across the silicone on either side of the LEDs.

I haven’t had the chance to test this iteration yet because I have not yet had time in the lab. I will report back with resistances and interesting things I learned once I have a chance to test it.

]]> http://nt.media.mit.edu/?p=1808 Tue, 13 Mar 2012 18:59:31 +0000 http://excedrin.media.mit.edu/newtextiles/?p=1808 Last year, I experimented with embedding small spherical magnets in an elastic fabric in order to simulate a controlled surface deformation:

With this assignment, I wanted to recreate a similar effect by embedding the magnets in silicone.

First I made a mold by laser cutting plexi and stacking it to get the inverse of what I wanted in the silicone:

Next, I cast silicone into that mold. Once cured, I removed the piece and inserted small spherical magnets into the pockets left behind by the mold.

I then used another plexi mold (without the raised points) to cast another thin layer of silicone on top of the piece embedded with the magnets and trap the magnets within the silicone.

Finally, I made a plexi frame to suspend the silicone/magnet piece vertically, allowing me to deform the surface freely from either side with an external magnet.

In action:

Another experiment with casting silicone:

I made the previous silicone piece by casting into the diamond pleated structure from last week (folded in mylar instead of paper):

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For the nonwoven textile project, I tested felting wool roving with aluminum wool as conductive material. In this quick test, I soldered a small LED to a crimp-beaded aluminum wool. It seems to light up and work! I liked the fact that everything can be felted into one material/surface; no need for stitching conductive thread, etc.

I decided to wet  felt a small plate and needle felt aluminum wool into two strands where I can attach series of LEDs. Pictures below show the felting process, where I layered two different colors of wool roving and used a bowl as a mold to felt the plate shape. 

After the bowl is felted, I needle felted two rows of aluminum wool. Since the aluminum wool doesn’t solder well, I added crimp beads where I wanted to attach LEDs to. Making sure that the LEDs are all aligned in the right direction, I soldered the LEDs to the crimp beads. And.. it should light up with the lilypad battery! Hmmm…. although individual LEDs light up when lilypad is connected individually, the row of LEDs do not light up all together. I’m guessing the aluminum wool is not conductive enough, or the wool fibers are shorting the circuit. Time to debug!

I wanted to recreate an abstract version of this painting using silicon and optic fibers. I first built a molt using Legos, I left holes where fiber optics should go. I then cut up several fiber optics pieces and scored cuts and holes.

After inserting the fiber optics into the Lego, I poured yellow and blue silicon over the fiber optics. Here’s the final product:

I then tested out how the fiber optics looked using a LED.

Video:

http://www.youtube.com/watch?v=lg-n265DU20

Rooms for improvements:

I really liked how the project looked, if I had more time, I would’ve made another one where the painting part could be less abstract and resemble the real painting more. I could also be more strategic in terms of where I put the fiber optics. I think the effects would’ve been better if I concentrated the fiber optics more and scorched more.

A few mili fluidic devices I made in 2.674 are below. They are fabricated with UV curing epoxy on glass which are both stiff materials, so they will not work for a soft device as required by the project.

Micro fluidic devices are usually fabricated with PDMS which is flexible, but the PDMS is bonded to glass to make the structure rigid. I did not have access to PDMS for this project, so I decided to use the DragonSkin silicone provided by the class as my base material.

My first test used straws to create a hole in a silicone part. This worked well to make a passage, but allowed for only  very limited geometry.

The channels needs to be produced in a two part mold for more intricate geometries.

In the conventional method, the PDMS is bonded to glass by exposing both surfaces to an oxygen plasma and the same process should work for silicone. Cured silicone is nearly impossible to bond to by conventional means, to the plasma treatment was a reasonable option.

I modeled the channels I wanted to make in SolidWorks and machined the mold for the silicone on a CNC mill.  I then molded the silicone in the mold and a flat panel for the top as seen below.

The plasma chamber pictured below was used to prepare the surface for bonding. The purple seen through the chamber window is the plasma. Unfortunately, the silicone did not bond.

I colored thread with thermochromatic ink (just dipped it in a cup with some liquid color). After it dried I used the bumps of the Lego bricks of the walls of the mold to create a grid with two layers of thread. The original idea was to put current on the tread but the tread wasn’t conductive enough, and I couldn’t get current with the power supply. I used the heat gun instead, and after few minuted of blowing hot air the threads “disappeared” completely. The silicone kept the heat inside for a long time (about 15 minutes), before the treads was visible again.

Before Heating the piece

After Heating the piece


Beads Casting
I made some experiments with casting over beads to discover what will be the flexibility, attributes, and texture of the surfaces.
1. surface with beads:

2. Surface with beads removed after the casting:

color dipping
I wanted to try making bubbles of color in the silicone right after I pour it into the mold.
I wanted to use a syringe, but the viscosity of the silicone was to strong, so it didn’t work.
I did manage to create this interesting drawing.

I made a composite with acrylic yarn and purple duplication polymer. First, I crocheted a fishnet pattern out of purple yarn.

Then, I mixed the polymer components 1:1 in two parts and poured it over the net in an acrylic tray. I wanted the yarn to get soaked with the polymer to see what kind of texture would result if the polymer got in between the yarn fibers.

The resulting textile has an interesting combination of smoothness from the polymer and roughness from the yarn texture.

In this next textile, I wanted to experiment with a composite that combines two-dimensionality and three-dimensionality, with balloons and duplication polymer. I inflated several latex water balloons and taped them to the bottom of an acrylic tray.

I then mixed and poured the duplication polymer into the tray. The polymer, when set, holds the balloon bases in place.

The resulting textile is a 2D sheet of polymer with 3D balloons protruding from the surface.

Unfortunately, the balloons slowly deflate after a few days. So, I suppose one could say this textile also has a temporal component.

My third textile probably doesn’t really go with this assignment, since it’s technically a woven material, yet it is made out of a non-woven “yarn” that is cast with duplication polymer. This isn’t strictly a composite by the traditional definition, but I would say it is a composite of techniques since it combines a non-woven fabrication process to make the yarn with a traditional weaving (or knitting) technique. My labmate makes these green “spaghetti rods” for his model experiments on rod mechanics (most recently, the mechanics of curly hair!). I thought it would be interesting to knit these rods into a textile. I made “yarn” with the duplication polymer using a syringe and plastic tubing. I taped the tubing to a long piece of 80/20 to hold it in place and poured the duplication polymer into a syringe. The polymer is then extruded from the syringe into the plastic tubing.

Then, the plastic tubing is cut away after the polymer sets. This is what the “yarn” looks like:

Then I used knitting needles to knit a small sample. This material was particularly difficult to knit with since the “yarn” is quite rubbery and doesn’t like to slide along the knitting needles.

This is what the finished sample looks like:

]]> http://nt.media.mit.edu/?p=1675 Tue, 13 Mar 2012 05:35:52 +0000 http://excedrin.media.mit.edu/newtextiles/?p=1675 For my nonwoven project, I wanted to play with casting solid materials in silicone, so I decided to cast different candies in the form of jewelry. At first I was not sure what kind of reaction silicone would have to sugars but it turned out that the silicone cured well around the sugary delectables.

I chose to use Twizzlers, Nerds, and Dots (Gum drops) as the candies i was going to cast and wanted to make some fashionable bracelets/bangles out of them. To get the right shape I first laser cut a mold out of acrylic that was about 1/2 inch thick.  To prevent any leakages in the mold, I bonded another piece of acrylic behind it so that the mold had a back to it.

I then poured silicone into the molds so that they were filled about half way, placed the candies in, and then poured more silicone on top to make sure they were fully coated. The Twizzler bracelet was a bit more difficult because of its texture so I had to make sure that I was covering all spaces in the mold.  I had some extra silicone so I cast a Swedish Fish candy and more nerds in a small rounded dish to make a pendant that could be worn on a necklace.

I let the silicone cure for a few hours, then pulled the bracelets and pendant out of the molds. I trimmed off any excess silicone using a sharp knife.  Unfortunately I damaged the end of one bracelet while pulling it out of the mold but overall they turned out looking great.

Here are some pictures of my process and the finished product.

Introducing the Walicon — A Wallet Made of Silicon. In addition to making a function piece, I also wanted to better understand several key things:

1. Whether or not it was possible to stitch into silicon
2. How paper and ink would react to silicon
3. How fabric and silicon could be utilized together in a stylistic way

Therefore in order to meet these objectives I ensure that I not only had silicon agents, but also fabric, a sewing machine, and a paper printed with the words Lallitara.

Key steps:

1. I started by first printing the Lallitara logo
2. I then created a model using legos in which I then poured the silicon mixtures. I ensure that the at the bottom of the mold, I had placed the lallitara logo
3. I then utilized the sewing machine to create the final product

Dried leaves in latex

Leaves in latex

Testing of LED on copper tape

The second thing I did after trying the latex was test the potential of a simple circuit using an LED, copper tape, and power (3.7V max). In my photo above my LED lit brightly and my simple circuit was a success.

Designs generated using Balla Grammar

I love the work of Italian futurist painter, Giacomo Balla, and last semester I developed a shape grammar of his work, i.e. a computational approach to the generation of Balla-esque paintings. I decided I would use one of my designs using his grammar as the design for my silicone cast LED circuit. I modeled the design to create 3-dimensional character and for cutting of the mold. below are images of the “stained window” design.

Model & render of the Balla grammar design

Design laser cut from Masonite

I soldered my LEDs unto copper tape (separately) for easier placement and working into the circuit.

At the back of my mold I drew the negative lines (red) and the positive lines (black) of the circuit as a guide. This would influence the direction in which I laid my LED’s for efficient wiring of the circuit to the positive or negative sides of the LEDs. See wiring and soldering below.

After installing my circuit with LEDs and securing my mold, I made my silicone mixture (equal parts of Part A and Part B) and poured it – it is very viscous – into my mold. The stipulated time for curing is 1.5 hours.

After de-molding I connected my silicone cast circuit to a power supply and voila! my LEDs lit up. In de-molding however, I damaged one of the electrical connections of my LEDs.

Click here for YouTube Video >>>

Lessons Learned:

• Think carefully about demolding – I hot glued for circuit onto the Masonite frame so that it would be secure. I originally wanted the circuit suspended in the silicone. This plan changed after fixing it to the Masonite frame.
• Demolding – thought I didn’t get to try it here with silicone, I would have tried PAM (spray cooking oil) on my Masonite for easy demolding.. I will next time I use silicone.
• Mixing of clear silicone – I wish there was some visual clue to know if your Part A and Part B of silicone was properly mixed (please invent someone). I mixed my silicone, and was careful to stir and not whip so as not to introduce too many bubbles in the mixture. There were some areas that did not cure properly, and it would be because of improper mixing of the two parts.

Vernelle Noel – Resources

• Website
• Blog
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• Youtube

This work by Vernelle Noel is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.