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KIT/NeptunLab

New Process Will Allow You to 3D Print Glass on Demand

KIT/NeptunLab
KIT/NeptunLab

The surge in affordable 3D printing in recent years has allowed hobbyists to craft everything from customized toys to hair to prosthetic duck feet, with the only limit being the creator's imagination. Now, researchers in Germany are close to achieving a technique that could revolutionize both 3D applications and glassmaking by giving us the power to 3D print glass.

In a study published in Nature this week, Karlsruhe Institute of Technology (KIT) investigator Dr. Bastian Rapp presented a way of manufacturing a “liquid glass” that can be manipulated with 3D printing software and then heated until it’s a useful solid. (Normal glass consists of melted sand made from sheets in molten tin vats.) By making the glass dispensable through 3D printing nozzles, Rapp believes we’ll soon be able to 3D print glass that’s of sufficient quality for lenses, mirrors, and even drinking cups.

Previous attempts to conceive of a new way of glass production via 3D printers haven’t resulted in glass smooth enough for widespread use, according to The New York Times. Rapp’s method, called stereolithography, uses glass nanoparticles and suspends them in a liquid that hardens under UV light. As the printer shapes whatever design the software calls for, the light turns the liquid into a solid; a final step in a heated oven further solidifies the glass and burns off any excess materials.

The end result is said to be identical to commercial silica glass. It’s expected that the process could make glass as prolific an element in 3D printing as plastic.

The glass is also clear enough that its potential uses include the kind of fine glass needed for commercial applications like smartphone lenses or computing-based components. And because software is able to create these elaborate designs and shapes, as opposed to time-consuming human effort, observers believe it will be substantially cheaper.

As part of their proof of concept, KIT ran off tiny glass pretzels, a honeycomb, and miniature castles to demonstrate the level of detail available with the technology. In normal glassmaking, acids and chemicals are typically needed to etch designs and shapes.

KIT asserts that this type of 3D printed glass doesn’t require specialized equipment and is feasible with conventional printers, though it will probably be some time before the technology becomes widely used. When it does, the applications will likely go well beyond expensive technology production; Dr. Rapp envisions a day when dropped glasses or smashed flower vases will be easily replaced with a quick 3D solution.

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The Origins of 12 Christmas Traditions
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iStock

From expecting Santa to fill our footwear with gifts to eating cake that looks like tree bark, the holidays are filled with traditions—some of which are downright odd, when you stop and think about them. Where did they come from? Wonder no more. Here are the origins of 12 Christmas traditions.

1. HANGING STOCKINGS

While there’s no official record of why we hang socks for Santa, one of the most plausible explanations is that it's a variation on the old tradition of leaving out shoes with hay inside them on December 5, the eve of St. Nicholas’s feast day. Lucky children would discover that the hay they left for St. Nick’s donkey had been replaced with treats or coins when they woke up the next morning. Another story says that St. Nicholas learned of a father who was unable to pay for his three daughters' dowries, so St. Nick dropped gold balls down a chimney, which landed in stockings hung by the fire to dry. But this appears to be a modern telling—traditional versions of the story generally have the gold land at the father's feet after being thrown through a window.

Regardless of what started the tradition, people seem to have realized the need to use a decorative stocking in place of an actual sock pretty early on. In 1883, The New York Times wrote:

"In the days of the unobtrusive white stocking, no one could pretend that the stocking itself was a graceful or attractive object when hanging limp and empty from the foot of the bedstead. Now, however, since the adoption of decorated stockings, ... even the empty stocking may be a thing of beauty, and its owner can display it with confidence both at the Christmas season and on purely secular occasions."

2. CAROLING

Though it may seem like a centuries-old tradition, showing up at people’s houses to serenade them with seasonal tunes only dates back to the 19th century. Before that, neighbors did visit each other to impart wishes of good luck and good cheer, but not necessarily in song. Christmas carols themselves go back hundreds of years, minus the door-to-door part. The mashup of the two ideas didn’t come together until Victorian England, when caroling was part of every holiday—even May Day festivals. As Christmas became more commercialized, caroling for the occasion became more popular.

3. USING EVERGREENS FOR CHRISTMAS TREES

Photo of a man carrying a Christmas tree
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Before Christianity was even conceived of, people used evergreen boughs to decorate their homes during the winter; the greenery reminded them that plants would return in abundance soon. As Christianity became more popular in Europe, and Germany in particular, the tradition was absorbed into it. Christians decorated evergreen trees with apples to represent the Garden of Eden, calling them "Paradise Trees" around the time of Adam and Eve's name day—December 24. Gradually, the tradition was subsumed into Christmas celebrations.

The tradition spread as immigrants did, but the practice really took off when word got around that England’s Queen Victoria decorated a Christmas tree as a nod to her German husband’s heritage (German members of the British Royal Family had previously had Christmas trees, but they never caught on with the wider public). Her influence was felt worldwide, and by 1900, 1 in 5 American families had a Christmas tree. Today, 25 to 30 million real Christmas trees are sold in the U.S. every year.

4. THE COLORS RED AND GREEN

As with many other old Christmas traditions, there’s no hard-and-fast event that deemed red and green the Official Colors of Christmas™. But there are theories—the green may have derived from the evergreen tradition that dates back to before Christianity, and the red may be from holly berries. While they’re winter-hardy, just like evergreens, they also have a religious implication: The red berries have been associated with the blood of Christ.

5. UGLY CHRISTMAS SWEATERS

To celebrate this joyous season, many people gleefully don hideous knitwear adorned with ribbons, sequins, bows, and lights. In the past, the trend was embraced solely by grandmas, teachers, and fashion-challenged parents, but in the last decade or so, the ugly sweater has gone mainstream. We may have Canada to blame for that: According to the Ugly Christmas Sweater Party Book, the ugly sweater party trend can be traced to a 2001 gathering in Vancouver.

6. LEAVING MILK AND COOKIES FOR SANTA

A photo of milk and cookies left for Santa Claus
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When we plunk a few Oreos or chocolate chip cookies on a plate for St. Nick, accompanied by a cold glass of milk, we’re actually participating in a tradition that some scholars date back to ancient Norse mythology. According to legend, Odin had an eight-legged horse named Sleipnir. Kids would leave treats for Sleipnir, hoping that Odin would favor them with gifts in return. The practice became popular again in the U.S. during the Great Depression, when parents tried to impress upon kids the importance of being grateful for anything they were lucky enough to receive for Christmas.

7. THE A CHRISTMAS STORY MARATHON ON TBS

If one of the highlights of your holiday is tuning in for 24 hours of watching Ralphie Parker nearly shoot his eye out, you’re not alone—over the course of the day, more than 50 million viewers flip to TBS. The marathon first aired on TNT in 1997, then switched to sister station TBS in 2004. This Christmas marks the 20th year for the annual movie marathon.

8. YULE LOGS


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Throwing a yule log on the fire is another tradition that is said to predate Christianity. As part of winter solstice celebrations, Gaels and Celts burned logs decorated with holly, ivy, and pinecones to cleanse themselves of the past year and welcome the next one. They also believed the ashes would help protect against lightning strikes and evil spirits. The practice was scaled down over time, and eventually, it morphed into a more delicious tradition—cake! Parisian bakers really popularized the practice of creating yule log-shaped desserts during the 19th century, with various bakeries competing to see who could come up with the most elaborately decorated yule log.

If you prefer a wood yule log to one covered in frosting, but find yourself sans fireplace, you can always tune in to Yule Log TV.

9. ADVENT CALENDARS

Technically, Advent, a religious event that has been celebrated since the 4th century, is a four-week period that starts on the Sunday closest to the November 30 feast day of St. Andrew the Apostle. Traditionally, it marked the period to prepare for Christmas as well as the Second Coming. These days, it’s mostly used as a countdown to Christmas for the religious and the non-religious alike.

The modern commercialized advent calendar, which marks the passage of December days with little doors containing candy or small gifts, are believed to have been introduced by Gerhard Lang in the early 1900s. He was inspired by a calendar that his mother made for him when he was a child featuring 24 colored pictures attached to a piece of cardboard. Today, advent calendars contain everything from candy to LEGOs.

10. EGGNOG

A photo of two glasses of eggnog
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It’s hard to imagine why anyone would be inspired to chug a raw egg-based drink, but historians agree that 'nog was probably inspired by a medieval drink called "posset," a milky drink made with eggs, milk, and sometimes figs or sherry. These were all pricey ingredients, so the wealthy often used it to toast with.

Eggnog became a holiday drink when colonists brought it over from England, but they found a way to make it on the cheap, nixing the figs and substituting rum for sherry. And how about that weird "nog" name? No one knows for sure, but historians theorize that "nog" was short for "noggin," which was slang for a wooden cup, or a play on the Norfolk variety of beer also called nog (which itself may be named after the cup).

11. MISTLETOE

Mistletoe has been associated with fertility and vitality since ancient times, when Celtic Druids saw it as such because it blossomed even during the most frigid winters; the association stuck over the centuries.

It’s easy to see how fertility and kissing can be linked, but no one is quite sure how smooching under the shrub (actually, it’s a parasitic plant) became a common Christmas pastime. We do know the tradition was popular with English servants in the 18th century, then quickly spread to those they served. The archaic custom once allowed men to steal a kiss from any woman standing beneath; if she refused, they were doomed with bad luck.

12. CHRISTMAS CARDS

A photo of J.C. Horsley's first Christmas card
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Exchanging holiday greetings via mail is a surprisingly recent tradition, with the first formal card hitting shelves in 1843. Designed by an Englishman named J.C. Horsley, the cardboard greeting showed a happy group of people participating in a toast, along with the printed sentiment, "A Merry Christmas and a Happy New Year to you.” A thousand of them were printed that first year, and because it cost just a penny to mail a holiday hello to friends and family (the card itself was a shilling, or 12 times as much), the cards sold like hotcakes and a new custom was born. Today, Americans send around 2 billion cards every year.

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10 Rich Facts About Wall Street
Twentieth Century Fox
Twentieth Century Fox

It’s often said that the love of money is the root of all evil. Wall Street could have easily turned this sentiment into a tagline. A gripping financial thriller, the Oliver Stone classic is a cautionary tale whose message is every bit as relevant today as it was when it was released 30 years ago today.

1. OLIVER STONE WOULD DELIBERATELY TICK OFF MICHAEL DOUGLAS BETWEEN TAKES.

“As a director, he really tests you,” Douglas said of Stone. Around two weeks after shooting had started, Stone showed up at the actor’s trailer and asked “Are you on drugs? Because you look like you’ve never acted before in your life.” Mortified, Douglas took a look at some footage they’d already shot. Yet, after diligently reviewing it, he could find nothing wrong with his performance. “I came back to Oliver and said … ‘I think it’s okay,” Douglas remembers. “Yeah, it is, isn’t it?” Stone replied.

Eventually, Douglas wised up to his boss’s overly critical act. “Basically, what he wanted was to ratchet up that much more nastiness in Gordon Gekko,” Douglas explained. “And he was willing … for me to hate him for the rest of that movie just to bring it up a little more.” 

2. WALL STREET WON BOTH AN OSCAR AND A RAZZIE.


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Douglas’s cold portrayal of the unscrupulous Gekko netted him an Academy Award for Best Actor in 1988. On the other hand, critics were thoroughly unimpressed by leading lady Daryl Hannah, who took home a Worst Supporting Actress Razzie.

3. GORDON GEKKO’S FAMOUS PHONE WEIGHED TWO POUNDS.

In one pivotal scene, Gekko rings Bud with a state-of-the-art mobile communication device. Specifically, it’s a Motorola DynaTac 8000X. Released in 1983, this brick-shaped cell phone was 13 inches long, weighed two pounds, and cost the equivalent of $8,806 in modern dollars. During the 2010 sequel Wall Street: Money Never Sleeps, the anachronistic gadget returned for a quick sight gag.

4. CHARLIE SHEEN CHOSE TO HAVE HIS REAL FATHER PORTRAY HIS FICTIONAL ONE.

“It was interesting having my dad play my dad,” Sheen said on the DVD's “making of” documentary. Wall Street’s most dramatic arc revolves around Bud and Carl Fox, who were played by Charlie and Martin Sheen, respectively. Stone had built a strong working relationship with the former on the set of 1986’s Platoon. So when the time came to cast Carl, he had the younger Sheen make the call, asking “Do you want Jack Lemmon or do you want your father?” “Oh, Jack Lemmon’s a genius,” the actor said, “but my dad’s my dad and he’s kind of a genius, too.”

5. SCREENWRITER STANLEY WEISER COULDN'T FIND INSPIRATION IN EITHER CRIME AND PUNISHMENT OR THE GREAT GATSBY.

Before the writer could get started, Stone gave him a little homework. Originally, the film was conceived as “Crime and Punishment on Wall Street.” When Weiser was brought aboard one fateful Friday, Stone told him to read Dostoyevsky’s novel over the weekend. “Not having taken an Evelyn Wood Speed Reading class, I went to UCLA and purchased the Cliffs Notes,” Weiser wrote in 2008.

But the literary exercise proved futile. “On Monday, I explained to Oliver that the paradigm for that masterwork would not mesh well with the story we wanted to tell.” In a flash, Stone hit him with another assignment. “Okay,” he ordered, “read The Great Gatsby tonight, and see if we can mine something out of it.” This time, Weiser simply rented the 1974 movie adaptation. Once again, though, inspiration eluded him.

Wall Street as we know it didn’t really start to take shape until after a change in tactic: When Gatsby led him nowhere, Weiser read everything about finance that he could track down and, along with Stone, “spent three weeks visiting brokerage houses, interviewing investors and getting a feel for the Weltanschauung of Wall Street.”

6. PARTS OF THE MOVIE WERE SHOT AT THE NEW YORK STOCK EXCHANGE DURING WORKING HOURS.


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Permission was secured with the help of Kenneth Lipper, a longtime Wall Street insider who also served as New York City's deputy mayor from 1982 to 1985. For the film, Stone brought him on board as the chief technical advisor.

7. TWO MONTHS BEFORE THE FILM’S RELEASE, THERE WAS A MAJOR WALL STREET CRASH IN REAL LIFE.

Historians now call it “Black Monday.” On October 19, 1987, the Dow Jones Industrial Average dropped by a staggering 22.6 percent. It was the largest single-day stock market decline of all time, with $500 billion suddenly going up in smoke. Wall Street would hit theaters on December 11, leading conspiracy theorists to wonder if Stone had seen the crisis coming and made his movie to exploit it. 

“I did not foresee the crash, as some people say, because if I had, I would have made a lot of money,” Stone quipped.

8. GEKKO WAS BASED ON THREE BIG-NAME FINANCIERS. 


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“If you need a friend, get a dog,” Gekko advises his young protégé. This quote was adapted from a remark that corporate raider Carl Icahn once made (which he had cribbed from Harry Truman). In 1985, Icahn became a notorious figure by taking over TWA airlines under the pretense of making it more profitable only to sell off its assets for his own gain. Gekko, no doubt, would’ve approved.

Wall Street’s charismatic antagonist also took cues from Asher Edelman, a financier and major league art enthusiast. Another source of inspiration was arbiter Ivan Boesky, who confessed to illegal insider trading in 1986 and ended up in jail in 1988 (more about him later).

9. STONE’S FATHER WAS A STOCKBROKER.

A survivor of the Great Depression, Louis Stone had a huge influence on his cinematically-inclined son. “The main motivation to make Wall Street was my father,” the director admitted. “He always said there were no good business movies, because the businessman was always the villain.” In the end, Wall Street was dedicated to the elder Stone, who passed away two years before its release. 

10. GEKKO’S BIG LINE IS NUMBER 57 ON THE AMERICAN FILM INSTITUTE’S TOP 100 MOVIE QUOTES LIST.

“Greed, for lack of a better word, is good” finished just ahead of “Keep your friends close, but your enemies closer” from The Godfather: Part II. Gekko might as well have been quoting Boesky: At a 1985 commencement address given at UC Berkeley, the trader said “Greed is all right, by the way. I want you to know that. I think greed is healthy. You can be greedy and still feel good about yourself.”

Newsweek later reported on the speech—and made a telling observation. “The strangest thing, when we come to look back,” the magazine argued, “will not just be that Ivan Boesky could say that at a business school graduation, but that it was greeted with laughter and applause.”

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