Sometimes the beginning of the year is a little bit … well … boring. Everyone is working out at the gym and eating healthy green foods, and even though the sun still sets at an ungodly hour, all the festive holiday parties are over.  This admirably disciplined January attitude is great for working off all the pfeffernüsse you shoved in your face and chased with rum-laced egg nog at your Aunt Betty’s house in December, but if you’re not careful all of this new-found rigidity and focus could negatively affect your work.  So if you’re looking to spice up your latest facade design and hey – maybe even your life in general this month, then take a gander at this intriguing “multi-layer, polymeric reflective film that reflects 95%+ of visible light” and that can be used to create snazzy chrome-like, multicolored, and metallic effects in plastics (Source: Inventables.com).

Image courtesy UT Materials Lab & 3M

Radiant light film contains no metal whatsoever, so it’s non-corroding, thermally stable, non-conductive, and won’t produce electro-magnetic interference; it’s a well-mannered material that manages to create a striking effect with a minimum of fuss.  Taking a cue from butterfly wings, the colors in the film are created NOT through the use of pigments but rather through a series of microscopic ridges spaced a few hundred nanometers apart. Variations in the spacing of the ridges produce a range of colors (blue to magenta to gold) though the reflection and interference of different wavelengths of light, and as a result the material appears to change hue as you adjust your viewing angle.

Radiant light film is nothing if not versatile: it can be “embossed, die cut, sheet slit, precision cut, surface treated, dyed, coated to be heat sealed, coated with adhesive, printed and extruded into plastics. It can be combined with suitable color substrates to produce various vibrant colors in both reflection and transmission” (Inventables.com).  Hell – you can even turn the stuff into yarn and knit it into a sweater if you’re so inclined, according to manufacturer, 3M.

UN Studio’s La Defense, Almere

Technology: 3M Radiant Colour/Light Film.
Using radiant colour film to create interference colour.

So far the film has found applications in home décor, packaging, automotive trim and accents, computers, mobile phones and advertising media, and inspired by UN Studio, I think we should wrap some buildings with it. And then let’s go have some cookies because we all knew I’d never make it to March let alone 2013 on this ridiculous salad-filled healthy diet and I’m sore from doing pushups.

WU XING

I have filed Radiant Light film under Water and Wood. It’s flexible, reflective, and it interviews well.

Get Radiant Light Film from Inventables.

Every once in a while someone sends me a materials-related question and I get to sit at a local wing joint on a rainy day, my non-typing hand covered in piquant buffalo sauce and stringy, ranch-coated celery fragments, watching multiple football games simultaneously while happily dispensing advice on subjects about which I may or may not have any expertise … and it is glorious. In the interest of sharing knowledge and offering a forum for people with actual experience and/or information concerning the question to contribute what they know (which I hope you’ll do in the comments section) please allow me to present a recent query and answer for your infotainment:

Dear Alli,

We are students of product design and are interested in knowing about the methodology used in bending bamboo or lamboo for shaping.

Can you pls how this is done–is it by air pressure or water pressure or by direct heating?

Saroj
India

Hi Saroj,

Although it’s technically a grass, bamboo acts a lot like wood, in that it performs well in tension and it’s fibrous and fast-growing. And just as with its arboreal cousin, people bend bamboo in order to make furniture, walking canes, or perhaps they bend it for more complicated reasons such as in order to feel capable of imposing their will on the natural world. And from what I can tell, all of these bending operations, whether the object of your deformation is a piece of plywood or a length of bamboo, require the application of heat.

Image courtesy made-in-china.com

While I have seen people steam the bamboo or apply heated, wet rags then bend and clamp it into position once the material has absorbed enough moisture to become pliable, I think it’s also possible to just blast the stuff with a blowtorch. (I found a highly instructive video of a craftsman in Mexico bending bamboo using said tool, upon which I plan to base this advice). I’ll include the video but for those of you on YouTube restriction, here’s how it’s done:

First, the bamboo is rotated rapidly and heated with a blowtorch that the craftsman moves continuously, allowing him to apply heat to the entire length of the bamboo stalk without scorching it. He polishes the stalk with a rag then applies heat a second time, as though to lock in the polish.

Next, one end of the stalk gets sealed off and the hollow tube is filled with sand. I think the sand acts like a flexible internal reinforcing for the bamboo as it bends, preventing it from splitting, checking, or creasing as it bends. The sealed end is placed in a clamp, whereupon more fast-moving blowtorch heat gets applied as the craftsman bends the stalk into position.

After the bamboo has cooled, he is able to unstopper the ends and drain the sand out; and BAM! that craftsman has himself a perfectly curved piece of bamboo.

Lamboo, a material I have written about before, which is basically glu-lam made from bamboo, can also be bent, although I’d imagine that the process depends on the characteristics of the resin involved in the manufacture of the material, as well as how it’s configured etc.

There is also Bendywood, a sort of permanently flexible, slightly dehydrated wood product. I’m not sure if similar techniques could be applied to bamboo but it would be fun to try!

Saroj, I hope that this answers your question or that it at least provides some content for other informed people to disagree with or correct in the comments!

Sincerely,

Alli

WU XING:

I have filed this Q&A Special under WOOD because that is where I always file bamboo. HAH!

Yesterday I bent over in the attempt to tie the absurdly bright purple shoe laces on my almost offensively bright purple sneakers and made a startling discovery: I’m not as flexible as I used to be.  In fact, the overwhelming tightness of my hamstrings makes your standard British upper lip look positively floppy; and as I fired up my smartphone to schedule some emergency yoga I was reminded that I had yet to share an amazing new fully stretchable OLED display recently developed at the University of California, Los Angeles, a place where they know a thing or two about screens.

OLEDs or Organic Light-Emitting Diodes are great technology for screens primarily because they work without a backlight and can display deep black levels for high contrast.  OLED displays can be manufactured thinner and lighter than liquid crystal displays (LCDs) and “in low ambient light conditions such as dark rooms an OLED screen can achieve a higher contrast ratio than an LCD, whether the LCD uses either cold cathode fluorescent lamps or the more recently developed LED backlight. Due to their low thermal conductivity, they typically emit less light per area than inorganic LEDs” (Source: Wikipedia). What it all boils down to is that OLEDs are the bees knees. FACT.

Image courtesy wired.com

Once researchers saw how thin they could make OLEDs it was only a matter of time before people starting thinking about how to make them flexible. Stretchable electronics open up a world where video displays get rolled up and stuffed in your pocket, electronic sheets drape like cloth, electronics grow and shrink on command, and the mighty condor gets taken off the endangered species list.

Early attempts at stretchable electronics resulted in prototypes that connected rigid LEDs with stretchable material and others that bent but couldn’t stretch. The challenge researchers faced was how to ensure that the electrode could maintain connectivity while being deformed since many conductive materials can’t stretch nearly as far as one might like.  Enter the humble yet versatile carbon nanotube: it’s stretchable, conductive, appears transparent in thin layers, and it usually picks up the check after lunch dates.

The fly in the nanotube ointment, so to speak, is the fact that carbon nanotubes must be attached to a surface; the attachment can be tricky to pull off since when applied to a plastic backing nanotubes have a tendency to slide off or even slide past each other when the backing is stretched. To evict said proverbial fly from said proverbial ointment, the UCLA researchers created a carbon nanotube and polymer electrode layered on a stretchable, light-emitting plastic.

The researchers “coated carbon nanotubes onto a glass backing and added a liquid polymer that becomes solid yet stretchable when exposed to ultraviolet light. The polymer diffuses throughout the carbon nanotube network and dries to a flexible plastic that completely surrounds the network rather than just resting alongside it. Peeling the polymer-and-carbon-nanotube mix off of the glass yields a smooth, stretchable, transparent electrode” (Grifantini).  I imagine that the carbon nanotubes embedded in the plastic stretch at roughly the same rate, and that the plastic keeps to itself mostly and doesn’t interfere with the ability of the nanotubes to conduct electricity.

Image courtesy pcworld.com

The team sandwiched two layers of carbon nanotube electrode around another plastic that emits light when current runs through it.  Researchers obtained a laminator from a local office supply store to press the layered device together so that it could be handled safely in the presence of electric current.  As an aside, we did the same thing when we screen printed an electroluminescent lamp in Switzerland this summer and were hoping to not get electroshocked by the circuits. (More on that soon).  In contrast to our electroluminescent display, the flexible OLED created by the UCLA team can be stretched by as much as 45 percent while emitting a colored light.

Their prototype is a two-centimeter square that emits a one-centimeter square brilliant sky-blue light that stretches like silly putty until it loses conductivity due to being stretched too far or too many times (Grifantini).  The researchers also made a prototype using silver nano wires (which are more conductive than nanotubes) that exhibits similar stretching properties but is even more conductive.  Their layered approach is a great idea, not least because it’s easy to imagine how the process could be scaled up for production.  Now if only those scientists could help me with my hamstrings….

WU XING:

I have filed stretchable OLEDs under Water, Wood and Fire because they’re flexible, stretchy, and they light up.

Cited:

Grifantini, Kristina. “The First Fully Stretchable OLED.” Techreview.com 08/26/11. Accessed 10/05/11. URL.

Watch video: Stretchable OLED – Tech Review

There’s this place where I live called “Jimmy’s Food Store” and it is, as you might expect, a store where food is sold.  But oh what food it is!  Italian comestibles dripping with Italian deliciousness, sold with Italian gusto to Italians and non-Italians alike.  At Jimmy’s Food Store you can get an Italian meatball sandwich that will bring tears to your eyes. You will literally be crying as you eat it because it is so tasty, and you’ll be crying after you’ve eaten it because you’ll be so sad it’s gone.  I just started crying quietly at my desk just because I am thinking about it, actually.

If there is a drawback to Jimmy’s meatball sandwich (and please note that when I say drawback this is like pointing out that Miss Universe had on one too many fake eyelashes at the last pageant) it is that you receive it in a Styrofoam container.  I remember learning that it takes something like nine billion years and a thermonuclear explosion for Styrofoam to break down and return to Earth, and that even as it does so it is poisoning things and wreaking havoc and stealing your purse at gunpoint. It is bad stuff.  And even if you accept the fact that it has some good points (is a cheap insulating material that basically lasts forever) the Styrofoam containers at Jimmy’s are evil because they MAKE THE SANDWICH A LITTLE BIT SOGGY IF YOU DON’T OPEN IT RIGHT AWAY.

Image courtesy ecolect.net

I starting thinking about this while eating lunch at Jimmy’s last week because I had come across information about PaperFoam, which is an injection-molded cellulose fiber-based packaging material.  Paper foam is itself made from recycled paper, and its properties are similar to thin Styrofoam or pulp in packaging applications.  According to Ecolect, “the product is extremely lightweight which lowers the transportation costs, and consumers can discard [it] with paper recycling or in the trash as it easily biodegrades…  PaperFoam CD packaging, for example, has an 85% lower carbon footprint compared to traditional, plastic jewel-case CD packaging.”  The product is produced in the Netherlands, Denmark, the United States and Malaysia.

So I am thinking that Jimmy’s needs to develop a PaperFoam extra special vented meatball sandwich container. It would be biodegradable, prevent the sandwich from getting soggy, and keep it warm at the same time due to its insulating properties.  And for those of you wondering how this is relevant to architecture – you can’t build anything on an empty stomach!

WU XING

I have filed this material under WOOD because it is made of tree fibers.

Cited:

“Check Out Paper Foam, an Amazing Material!” Ecolect.net. Accessed 10/5/11. URL.

There are three types of people in the world: those who carefully transport insects and arachnids out of the building on sheets of paper, releasing them into the wild to roam free, bite innocent people, and reproduce; those who whip off their hard-soled shoes and gleefully smash anything with an exoskeleton that happens to wander within range; and those for whom the thought of a particularly nasty bug is enough to inspire a scream-enhanced instinctive high-speed run headlong into another room.

I belong to the last category, and thus it is with great trepidation and reluctance that I write about a new body of research out of the University of Akron that examines a pair of spider glues with useful properties.

I’ve read about work people are doing with spider silk threads (the silk tends to be amazingly strong – much stronger than kevlar, for instance, which is the material Superman would have adopted as his benchmark had it been more prevalent back in the day). But until recently I hadn’t stopped to think about what makes spiderwebs such a menace to society and to gnats, namely: they are sticky.

Image courtesy socypath.com

So as it turns out, to my abject horror, there are at least two general types of web-weaving spiders and they use the same set of glands to produce two different types of sticky silk-coating glue.

The first type, orb-weaving spiders, have been around pretty much since the dawn of time, and they produce something called viscid glue, a “glue that acts like a viscoelastic solid. Highly humidity-sensitive, this glue expands in magnitude and demonstrates a monotonous increase in elasticity under increased humidity. The glue also displays a decrease in surface adhesion that results in optimal adhesion at intermediate humidity” (physorg.com). Viscid glue can become stickier or less sticky depending on the humidity level.

The other type of spider, your garden variety cobweb-weaving spider,  is a direct descendant of the orb-weavers but produces gumfoot glue, an adhesive material that differs in structure, properties, and response to humidity.  Gumfoot glue “acts as a viscoelastic liquid that is resistant to changes in humidity, consequently maintaining constant elasticity and adhesion” (physorg.com).  So even when these spiders live in New Orleans or Hotlanta, the glue they produce maintains a consistent level of stickiness.

To figure out how glue from the two types of spiders differed, the research team took individual drops of glue and stretched them at different humidity levels. Observing that viscid glue behaved like a viscoelastic solid and that the gumfoot glue behaved like a viscoelastic liquid, the researchers designed a polymer model of the glue droplets to understand the mechanisms at work behind the responses.

Image courtesy coolphotoideas.com

Understanding the behavior patterns of natural biomaterials, such as spider glue, provides us with insight we can use to develop smart materials and devices that may undergo changes in dimension, properties, and function in response to changes in the environment.  Investigating changes wrought by evolution provides us with a means of advancing biomimetic research (research that seeks to understand and mimic nature, Leonardo DaVinci-style).  This line of thinking could lead to new adhesives with applications in buildings in humid environments, among other things – and that is why I braved a “spider” keyword Google search in order to illustrate this post.

WU XING:

I have filed this adhesive under WOOD and WATER, for reasons known only to myself.

Cited:

“Spider Silk Glue Inspires Next-Generation Technology.” Physorg.com 7/22/11. Accessed 7/22/11. URL.

Vasav Sahni, Todd A. Blackledge & Ali Dhinojwala. “Changes in the Adhesive Properties of Spider Aggregate Glue During the Evolution of Cobwebs.” Scientific Reports 7/21/11. Accessed 7/22/11. URL.

Even thinking about glass fiber reinforced plastic (GFRP) makes me itchy. The reason for this is that the glass strands involved with this material are so fine (by which I mean that they are extremely thin and tiny, rather than that they are really really ridiculously good looking) that they get caught in your skin and clothes and become profoundly irritating, after the manner of a wood splinter or Brett Favre.

Image courtesy taiwan.xpshou.com

At the Actuated Matter Workshop in Zurich, we were introduced to a particular configuration of GFRP developed by Loop.pH, which I have dubbed, “Lo-mein GFRP” due to its noodle-esque appearance. The material is much stronger and stiffer than pasta, however, which allowed us to bend it into circles and secure the shapes with small brass tubes.  I found out that if you bend Lo-mein GFRP too far, it fails spectacularly, emitting a quiet yet somehow disdainful pfffffft noise and spraying glass fibers everywhere like needle-sharp, toxic fairy dust.

GFRP circles can be intertwined and woven into a kind of structural textile that can take various forms according to the number of circles combined in any particular configuration.  For example: if you take one circle and surround it with five other circles and connect all of them, you will produce a spherical construction; if you surround your starting circle with six other circles you get a flat surface; and if you ring your circle of origination with seven other circles you will achieve a floppy but endearing hyperbolic paraboloid (aka saddle shape).

Spheres, circles, and saddles can be combined to form almost any surface you can imagine, from a column (a flat sheet, rolled into a cylinder) to a triply periodic minimal surface constructed entirely of conjoined saddles.  The construction we built at the workshop to support our sound, light, and movement modules was a just this sort of minimal surface, and it was glorious.

Invisible itchy splinters aside, I enjoyed working with GFRP because it’s lightweight, extremely strong, and delightfully robust.  It’s not as strong or as stiff as carbon fiber but it’s a heck of a lot cheaper and it’s much less brittle.  The material is commonly used for boats (holla!), automobiles, hot tubs, water tanks, roofing, pipes, cladding and external door skins, and less commonly it is used to make interactive architecture.

Please check out this video featuring the final installation and make it a great day!

Actuated Matter Workshop from materiability on Vimeo.

WU XING:

I filed GFRP under wood because it’s bendy and fibrous. And because I call the shots around here.

I believe it started out with casual smart phone use in social situations – it was really convenient to communicate via text message and we all liked watching the Honeybadger video you found on YouTube while we were waiting for the bus.  I’ll admit I didn’t think anything of it when you mentioned you made 4,506 Facebook friends and had created an equal number of Google+ Circles.  I didn’t blink when you said you were also monitoring sixteen email accounts while a writing a blog about micro-finance, although in retrospect that seems like a lot.

Image courtesy bjcblog.wordpress.com

I started to worry when you let it slip that you were dabbling in electronics and that you had hacked a Microsoft Kinect. You started hanging out with a different crowd and you changed your behavior dramatically, staying up all night writing code.  You didn’t seem to care that you lost your job, and for the past month you’ve only emerged from your apartment to buy donuts and stepper motors.  You developed what I consider an unhealthy fascination with the movie Iron Man, even going so far as to characterize the sequel as, “an awesome flick.”

Image courtesy NCSU

But when you mentioned you were trying to get your hands on a biocompatible electronic device recently developed by researchers at NC State, I got really worried. I’m so worried I called your Mom, and now she’s worried too – and she’s making it your Dad’s problem. What on earth do you want with a soft, flexible memory device the consistency of Jell-O that functions in wet environments SUCH AS THE HUMAN BODY!?!?! I mean, this stuff could potentially interface with biological tissue!

The only thing I can think is that you are becoming a Cyborg.

I did a little digging, and I found out that the new device functions like a memristor, which is (as if you didn’t know):

“a passive two-terminal electronic component in which there is a functional relationship between charge and magnetic flux linkage. When current flows in one direction through the device, the resistance increases; and when current flows in the opposite direction, the resistance decreases, although it must remain positive. When the current is stopped, the component retains the last resistance that it had, and when the flow of charge starts again, the resistance of the circuit will be what it was when it was last active” (Wikipedia).

From what I can gather, the prototypes the researchers developed are flexible and can exist in two states: conductive or resistive. That’s important because two states could correspond to the 1s and 0s in binary computer code, and researchers are working on a way to program the devices, meaning that one day they might be able to interact with your neurons.

So tell me – and be honest: are you or are you not working on some kind of human/computer fusion project using yourself as a lab rat? Because if you are, I think we need to find you a support group.

WU XING:

Filed under wood due to the flexibility and hard/soft kind of quality.

Cited:

Dillow, Clay. “New Memory Device Feels Like Jell-O, Could Work Inside Your Body.” Popsci.com 7/14/11. Accessed 7/21/11. URL.

NCSU: Soft Memory Device Opens Door To New Biocompatible Electronics

Say what you will about the 1990’s, the decade produced some severely under-appreciated and entirely too short-lived cultural moments: I mean, Hammer pants? Titanic? Come on – you know you loved it!  Another phenomenon of the 1990’s that in some ways is slightly less exciting than the OJ Simpson trial, but which has stayed with us to this day is: green-tinted glass.

Image courtesy metaefficient.com

No one knows exactly how it started, but I imagine that sometime in the 1990’s, an architect somewhere in the world specified green-tinted glass for the fenestration on a prominent building. This building was probably published in a print magazine that a lot of other architects read, and somehow, without even knowing what was happening, they all suddenly wanted to use green glass on their projects too.  I completely understand: the exact same thing happened to me when I was reading Elle and saw that Heidi Klum decided to cut bangs (and yes, mine are still growing out).

Image courtesy instyle.com

What if there was a way to have your green glass cake when it felt trendy, and then not have the same cake twenty years later when it was moldy and dated, and kind of sad looking?  I think perhaps there is!

I recently learned that a University of Connecticut scientist has developed a method that allows films and displays to change color.  The obvious application for this technology is sunglasses, and everyone from Hollywood stars to the U.S. military are interested in lenses that respond to changes in the environment to make it easier to see (or be seen).

Typical transition lenses use photochromic films, which are sheets of polymers that change color when light hits them. The new color-changing technology uses electrochromic lenses; these are controlled by an electric current passing through them that adjusts when triggered by a stimulus such as light (Physorg.com). The arrangement is similar to a double-pane window with a gel sandwiched between the glass.

Image courtesy physorg.com

That’s what got me thinking that this material, which can change color as quickly as electricity can travel through it (ie instantaneously) could be great for buildings.  The polymer used by the scientists creates less waste and is less expensive to produce than previous mixtures, which is good because for an architectural application, you’d need a lot of it!

WU XING:

I have filed this under fire because electricity creates the color change, and under wood, because it’s a polymer.

Cited:

“A Better Way to Photo Gray: New Technology Allows Lenses to Change Color Rapidly.” Physorg.com 07/12/11. Accessed 07/15/11. URL.

I resent the noise of the printer, printer jams, shaking the toner cartridge, the harsh chemicals involved, and the amount of electricity it takes to print on a sheet of paper. I resent those things with the heat of a thousand suns.

But … just when I believed that I had calcified in my negative stance on all forms of printing, I learned that MIT engineers recently revealed a process they’ve developed to produce printed solar cells.  Their flexible cells can be printed on paper or fabric and folded over 1,000 times without losing efficiency, and they’re not energy-intensive to produce!  I was cautiously optimistic: maybe, I thought, printing doesn’t have to be completely evil?

Photos: Patrick Gillooly/MIT

The creation of typical solar cells involves exposing substrates to intense chemicals and high temperatures, which necessitates a whole lotta energy consumption.  MIT’s new fancy solar cells “are formed by placing five layers of material onto  a single sheet of  paper in successive passes. A mask is utilized to form the cell patterns, and  the entire printing process is done in a vacuum chamber” (Singh).  Fabric and paper substrates weigh less than the glass and other heavy backing materials that are typically used, and researchers think that they’re well on the way to developing scalable cells for use in photovoltaic arrays.

So here’s what I’ll say: the day my office printer can power itself by printing out solar cells is the day I will let go of these negative emotions and learn to forgive.

Click  here to see the technology in action (via Inhabitat).

WU XING:

I have filed MIT’s solar cells under water (because of the gentle process) and wood (because they’re flexible and can be printed on paper). And also, privately, under awesome.

Cited:

Singh, Timon. “MIT Unveils Flexible Solar Cells Printed on Paper.” Inhabitat.com 07/11/11. Accessed 07/12/11. URL.

No really – it isn’t like learning about the War of Jenkins Ear, where you have to imagine being alive in the 1700’s and fighting with a large group of Spanish and British soldiers and it’s a bit of a stretch. You know what compression when you attempt to balance a pile of textbooks about colonial military campaigns on your head and your neck shortens, and you understand tension because you actually feel it when you pull on a locked doorknob.

Image courtesy wikimedia commons

So far I haven’t worked on any projects like the Denver Airport, where tension and its expression are major elements of the design. But I am working on a competition entry that will incorporate wind-resistant architectural fabric, and research for that project caused me to dig through my lovely ARCHITERIALS submissions inbox where I found product information from Tensotherm with Nanogel®, developed by Birdair, Cabot Corporation and Geiger Engineers.

Tensotherm is a tensile fabric material that insulates like standard roofing, although it can be made translucent if you’re interested in letting light shine in.  According to the product literature, “Tensotherm is comprised of two layers of PTFE fabric membrane with a layer of Nanogel aerogel sandwiched between the two layers. PTFE, or polytetrafluoroethylene, is a Teflon®-coated woven fiberglass membrane that is extremely durable and water resistant; it is capable of withstanding temperatures from -100°F to +450°F, immune to UV rays, and waterproof.” The aerogel layer is as light as a feather and as an insulator it makes whale blubber look pathetic (please do read this post for more on the awesome characteristics of aerogels).

Image courtesy birdair.com

The product is manufactured in Tijuana, Mexico, but unlike strong narcotics arriving daily from South and Central America, Tensotherm is suitable for use as roofing in stadiums, arenas, schools, convention centers, transportation facilities, retail facilities and more. Don’t use it for open-air structures, as it’s not suited for the application.

Image courtesy birdair.com

While it’s hard to know what goes in to the manufacturing process, translucent Tensotherm could contribute to a green building strategy that incorporates daylighting, and if it’s indeed an effective insulator it could reduce heating and cooling loads in buildings.  Another benefit of a lightweight, tensile roof is the fact that support structure can be smaller in size; this reduces expenditures on shipping and installation.  The system produces very little job site waste and the fabric can contribute to the acoustic environment.

Have you used Tensotherm or similar products in your work? Let us know what’s what in the comments!

WU XING:

I have filed Tensotherm under Wood because it’s great in tension.