Innehållsförteckning för December 2019 från Popular Mechanics

COURTNEY LINDER SENIOR NEWS EDITOR Big fan of buying your dad’s old vinyl at Goodwill. For Healthy Plants Simply whip up a mixture of about one quarter leftover coffee and three quarters water and add it to your watering can or mix used grounds with the soil while repotting. The nitrogen in coffee aids in healthy growing. My Favorite App Libby, hands-down. All you have to do is enter your credentials from your current library card and you can place holds on or download audiobooks and ebooks, instantly. The library has always been cool, but in a digit al world, it also has to be accessible 24/7. PRODUCTS I’M USING RIGHT NOW 1 Dagne Dover Allyn Tote in Oxblood Every ambitious woman (and dude!) needs a bag that’s both sleek…

THIS YEAR I PLAYED AS many new board games as I could get my hands on. And I’m not particularly picky, so if it was popular, I played it. If it had a fascinating theme or novel game mechanic, I played it. And if other reviewers said they loved it, I played it. I only avoided games that required any sort of phone or app. I tested just shy of 40 new games, published from December ’18 to October ’19 (when this issue went to print). I played most of the games in Rwanda, where I work in international development. There are no personal mailboxes in the country, so I had the games ferried over in suitcases, one visitor at a time. Often they were the only copies in the…

THERE’S A PHASE COLlege students go through where they decide cheap, clear liquor needs an upgrade. But what, really, can an aspiring dormroom mixologist do with a non-discerning palate, limited funds, and not enough time? Ah yes. Infuse. Just throw Skittles or frozen blueberries or any other easily accessible sweet accoutrement into the plastic handle and wait. The resulting concoction is probably awful. It will be consumed anyway. Don’t be ashamed if you went through that phase. You may now have disposable income to buy fancier bottles, but that does not mean you should quash that adventurous spirit—you know, the same one that drove you to throw Pop Rocks into Smirnoff. Harness that desire to meddle with your liquor cabinet and you can create some truly wild and delicious drinks.…

MATHEMATICIAN ANDREW BOOKER was searching for topics to present at his children’s math club when he stumbled across a YouTube video about the sum-of-three-cubes puzzle. “It was a case of serendipity,” the University of Bristol mathematics professor says. The video—produced by the popular YouTube channel Numberphile—led him to solve a curious equation that has stumped mathematicians for decades. In 1825, mathematician S. Ryley proved in the magazine Ladies’ Diary that any fraction can be represented as the sum of three cubes of fractions. Mathematician Louis Mordell took the puzzle a step further in 1953, when he questioned whether the same type of solution could be found for x3+y3+z3 = k, a diophantine equation, which involves only positive and negative integers. He started with the number 3, and the hunt was…

A NO-BRAINER BUILD Find a log at least 8 inches in diameter and 16 inches long (make sure both ends are flat) and stand it upright. Using an axe or chainsaw, make 2 or 3 cuts down the length of the log as if you were slicing a pie, stopping 5 inches above the base (some wire will hold the log together if it starts to fall apart). Stack kindling atop the log at the intersection of the cuts and light. It will fall through the cracks as it burns, lighting the log from the inside. AN ULTRA-FOCUSED FLAME Traditional fires can take hours to produce embers suitable for cooking or warming your camp. But a Swedish fire log’s contained heat makes it hot enough for cooking in as little…

THE PREVAILING TREND among boots this winter? Lightweight, low-profile, comfortable designs that don’t sacrifice performance, whether you’re wearing them to tromp through deep snow drifts, get out for a quick hike in what little sunlight there is, or simply stay upright on icy sidewalks. Here, we review the best snow, casual, and hiking boots this winter. Before hitting the pavement and the trail, we consulted with experts, read customer reviews, and searched for the season’s top options. In the course of testing, we evaluated the cost, weight, traction, support, comfort, water-proofing, durability, style, and (in the case of the dedicated winter boots) warmth of each pair. We hiked for hundreds of miles on dirt, grass, and gravel trails, on sunny days and after rainstorms, across the Northeast and national parks…

WHAT EVER YEAR you’re reading this, the new iPhone is awesome. It always is. Same with the new Samsung Galaxy, and Bose’s new noise-canceling headphones. But right now, just before 2020, the improvements between versions are becoming less obvious. In the case of the iPhone 11, the cameras are a big advance. But for the majority of us customers, last year’s model will serve us just as well as the new one. That’s why, when I need something like a phone or laptop, I almost never buy it new. You should do the same. I’m not talking about going on eBay or Craigslist or letgo for used tech. Even if you know what to look for and what prices are fair, the time cost of doing all the quality control…

IF YOU WANT A NEW SILVERado, and you’ve got an extra $2,495 to spend on upgrading from the 5.3-liter V-8 engine, then Chevy has a dilemma for you. For that money, you have your choice of a 6.2-liter gas V-8, or a 3.0-liter Duramax diesel inline-six. So, which one do you get? Superficially, the choice comes down to horsepower or fuel economy. A 4x4 with the V-8 gets 17 mpg combined, while the diesel gets 25 mpg combined. On the other hand, the V-8 makes 420 horsepower to the diesel’s 277. The gas truck is quick and thirsty, while the diesel is slower and thriftier. But that’s not all there is to it. While the big V-8 is unquestionably quicker when you’re going wide-open-throttle, the two engines don’t feel wildly…

IS IT ACTUALLY the Titanic at the bottom of the ocean? No one is denying that a ship really sank in the icy waters of the North Atlantic on April 15, 1912. Or that approximately 1,500 passengers aboard perished. However, there are some who suggest that the White Star Line, the ship’s parent company, pulled a fast one on the public in an insurance scam that ended up going horribly wrong. These theorists claim that instead of the Titanic, a sister ship in White Star’s fleet was the one that now sits at the bottom of the ocean. The strangest part: The idea isn’t as far-fetched as you might think. THE HEYDAY OF BIG SHIPS The British White Star Line had stiff competition in England and across the globe. Locally,…

4000 BCE Ancient Greeks mined the toxic mineral asbestos—named for their word meaning “indistinguishable”—and used its fibrous crystals to make wicks for candles and lamps. 450 BCE Greek historian Herodotus reported the use of asbestos shrouds in funeral pyres to preserve a body’s ashes. Meanwhile, the Romans sewed asbestos fibers into tablecloths and napkins. 755 King Charlemagne of France ordered an asbestos-woven tablecloth to prevent accidental fires (a major party foul) at his many feasts and fêtes. 1725 As the Italian government doled out asbestos-fibered bank notes to their citizenry, Ben Franklin touted a purse made of the fireproof material during a visit to England. 1821 French chemist Joseph Louis Gay-Lussac fused boron salts with ammonium phosphate to create a fire-protective agent for clothing, but the substance’s high solu bility…

When we brainstormed an element to take this story over the top, someone joked that we should build a flamethrower. After the laughter and legality questions subsided—flamethrowers are legal in 48 states (they’re banned in Maryland and require a permit to be owned in California)—I said, “I can build one.” And with that, this project became as much about building a flamethrower as about my becoming (only somewhat reluctantly) the envy of my friends, the chief concern of my loved ones, and maybe the top name on a watch list somewhere. The basic theory of flamethrower operation is simple: An inert gas pressurizes a vessel holding fuel, the fuel is released via a valve, and the fuel is ignited as it exits an orifice. The biggest danger is the risk…

Farm to Feet Cascade Locks Socks Made in North Carolina with materials produced in the U.S., Farm to Feet’s Cascade Locks three-quarter crew sock fits securely and comfortably, with padded zones from heel to toe that reduce rubbing and boost durability. The blend of nylon, moisture-wicking merino wool, and Lycra spandex flexes with your foot and offers slight compression from the lower calf down to the arch while still providing maximum comfort. $23 Sea to Summit Comfort Plus Self-Inflating Sleeping Mat Luxury sleeping pads might seem like an oxymoron to some, but the Comfort Plus delivers an exceedingly cushy place to rest at the end of the day. Three inches thick at full inflation, this self-inflating pad has a nonslip grip pattern on the bottom to keep it in place…

SPORT ATVS ARE AN endangered species. Back in the glory days of 2008, just about every ATV company bui lt a sport machine. But today’s ATV market is afflicted with an acute case of pragmatism, rife with blocky four-wheel-drives fitted with cargo racks and hitches. The implication seems to be that fun for its own sake is irresponsible—you use your utility quad to clear brush off the back 40; any entertainment is purely incidental. That’s why the 2020 Polaris Scrambler XP 1000S is so refreshing: It’s gloriously useless. The tow rating is zero. The Scrambler exists to turn gasoline into serotonin, end of mission statement. The Polaris approaches that mission a little bit differently than the other lonely sport ATV, the Yamaha Raptor. The Raptor, in either 450-cc or 700-cc…

ALMOST EVERY WAVE IS OVERHEAD WHEN YOU’RE LYING prone on a surfboard, but these waves? They tower four to six feet above the 13 riders on the water. The group—many of them first-time surfers—chatter nervously while gripping their boards. Then, a “Get pitted, bro!” erupts across the water from a smiling Roy Tuscany. He sits on a board, paddle in hand, “sharing the stoke” as he calls it. With every incoming set, every aborted ride in, every crash into churning foam, Tuscany doles out congratulations and high fives. The surfers are from all over the country. The ocean outside San Clemente is just another stop on a much larger journey. Somewhere along the way, each of them experienced a traumatic injury, often to the spinal cord or head, sometimes a…

Whether we’re staring into the depths of a campfire or watching a Space Shuttle burn 500,000 gallons of fuel as it rises off the launchpad, mankind’s obsession with fire is so innate we almost take it for granted. Yet fire has catalyzed the human race’s most significant innovations. It’s helped us survive. It’s helped us flourish. It’s given us one hell of a backyard toy (see “That’s Right: I Built a Flamethrower,” page 78). Yet the path that took us from hunching around a lightning-struck tree for warmth to carrying lighters in our pockets has many reminders of fire’s volatility—from the epic scope of The Great Chicago Fire to the explosion of the oil rig Deepwater Horizon. Fire comes with a big fat warning sticker, but nonetheless, it’s man’s most…

IF WINTER WERE JUST A matter of fewer daylight hours, most people could probably manage it okay. But it’s cold, too, making it both a psychological and physical battle. Many people respond by using a portable heater—a cheerful gadget that radiates June in the middle of January—in drafty rooms, home work areas, chilly entryways, or the office cubicle. These appliances are also perfect for lowering the thermostat elsewhere (saving you money) and heating only a select room. We called in a big batch—nearly two dozen heaters in all—and tested them to see how well and how safely they work. Our test appliances were divided into two broad categories: electric and fuel-fired. Some are fan-equipped, meaning they push heated air toward you and into the living space. Others are passive: They…