Innholdsfortegnelse for July 2019 i Popular Mechanics South Africa

HAVING NEVER REALLY thought about it, it was quite interesting to discover recently that the average walking speed for humans is around 5 km/h. On a Saturday not long ago, some friends and I took a relaxed mountain hike on the back of the Table Mountain range, and ended up covering close on 16 km – with our stops, we did the whole route in roughly five and a half hours. My iPhone told me I’d taken 24 118 steps in total, which just seems amazing to me. Legs and feet are remarkable things. My bedtime reading at the moment has been Christopher McDougall’s bestselling book Born to Run, which details how incredibly well-adapted our bodies are to walking, and more specifically, endurance running, even compared to some animal species…

ON THE WAY to Skydive the Ranch in Ulster County, New York, a pastoral expanse encompassing a shallow pond, a runway, and an aircraft hangar that houses a couple of 22-passenger Twin Otter aeroplanes, Red Bull-sponsored professional skydiver Jeff Provenzano (nickname Jeffro) assures me that he too was petrified on his first tandem dive. ‘We’re more likely to get hurt on the drive to the drop zone than we are during the jump,’ he says. Then he immediately makes an ill-advised U-turn in front of a speeding SUV. Over his 20 000-some jumps, Provenzano has performed stunts for movies, trained special-forces teams, and hung from helicopter struts as if they were tree branches. The man is unflappable in the face of the absurd. Later, when the door to our Twin…

AFTER LAST NIGHT’S STORM, it’s a good snow day. Every lift shack and snowcat, every delicate needle on every spruce, and every trail at Snowbird is covered with powder – perfect for morning ski runs. It’s also the perfect conditions for an avalanche. In groups of two and three, the Snowbird avalanche team hike in ski boots through fresh snow up to their knees, their backpacks full of one-kilogram hand charges the size of soup cans. Someone shouts, ‘Fire in the hole!’ then pauses briefly before tossing the slurry of explosives, listening carefully for any hastily shouted objection. The two-minute fuse burns for what feels like a lot more than two minutes. Is it a dud? BOOOOOOM! Snow rushes down the empty chute, just as planned. It roars through trees,…

Humans’ love of hot sauce is a bit of an enigma. It burns, after all, sometimes quite painfully, and our tongues are left struggling to navigate their way through the other flavours in our meals. But aargh, is it yummy! We’ve had a love affair with chilli for a long time, several thousand years in fact. There is evidence that the people living in what’s now called southern Mexico about 6 000 years ago cultivated chilli plants, and archaeological finds from ancient sunken ships have revealed what they think are containers that used to house hot sauce. And it’s not only been about flavour. Medically speaking, chilli was said to aid digestion and help with liver function, and it was also believed that beneficial endorphins were released when eating hot chilli.…

IT’S AN INESCAPABLE truth. All woodworkers need clamps, and lots of them – clamps of different sizes, shapes and types. But I don’t want or need clamps that are capable of crushing my workpieces. I want ones that are well made, with the intended purpose of holding two or more joinery pieces firmly together until the glue or adhesive has cured – nothing more, nothing less. It’s not often in the world of woodwork clamps that something truly revolutionary and intensely sensible comes around. The wooden hand screw, the spring clamp, the toggle clamp and the parallel jaw clamp are examples of designers thinking as craftsmen, as users of the product. It’s when this happens that great tools are born. German clamp company BESSEY has recently introduced its new GearKlamp…

• Always switch the router off, let it come to a stop, then retract it, before unclamping and moving the upper cradle to the next overlapping cutting position. • Ensure the router’s power cable is kept clear of the cradle at all times. If you can, try to suspend the cable from above, allowing sufficient travel for the router. • Do not get lazy and try to cut without firmly clamping the upper cradle to the lower cradle. This is vital. • Keep debris clear of the cutting area at all times. (I simply use compressed air to blow the area clean after each time I have moved the upper cradle to its new position.) • The Dimar router bit is a serious cutter, so pay attention to the rotational-speed…

HOW IT WORKS…

THE TRAIN RIDE was as uneventful as the dozens of others the man had taken from Washington, DC, to New York City. He watched the scenery change as he headed north, past Baltimore, along the Delaware River to Philadelphia, through Newark, then into the long, dark tunnel on the final approach to New York’s Pennsylvania Station. Throughout the trip, the device in his pocket – the size of a portable hard drive, all black, with a single button on the centre of one side and a blinking blue LED light above it – remained silent. After getting off the train, the man moved with the large midday crowd towards the entrance to the subway. On the uptown platform, standing near a dark-haired woman in her late 40s, he felt his…

Presidential records have expanded to now include emails and even tweets. The Obama Presidential Center recently announced it may not have physical archives at all. Caro has a few thoughts about such things: SMARTPHONES Researchers now snap pictures of documents, to read later. Would he have made the same discoveries reading papers on an iPhone? ‘Possibly. But I don’t believe it.’ CTRL-F An infrequent Googler, Caro allows that control+F (‘find’) is ‘the great help for researchers,’ letting them scan massive sets of documents for a specific subject. THE CLOUD Getting government papers requires bureaucratic approval. Online archives could be worse. ‘What’s worrisome to me is that somebody has to decide what’s digitised,’ Caro says.…

The project area is located within a wide region of plateau basalt belonging to the Karoo Group of the Jurassic period, said to be around 170 million years old. The project area reveals a 1 000 metre-thick lava pile, underneath which is situated a north-east-trending, 70–80 km-wide channel of sediments and basalt. The channel is bounded by Precambrian rocks to the south-east and north-east. In the southern part of the channel, the major north-east-trending Deka Fault – which meets the Zambezi River about 75 km downstream of the Batoka site – separates the basalts from the Karoo sediments below. South-west of Victoria Falls and south of the dam site, the plateau basalts are covered by newer, sandy sediments blown there by the wind, as well as alluvium. The basalts form…

Tandem You’ll be attached via harness to an instructor who will do all the hard parts for you. All tandem skydiving rigs use a drogue chute (it looks like a fat balloon) to reduce the terminal velocity of two people. Static line Often used during military training. You’ll jump with a cord attached to the aeroplane hanging out of your backpack. The cord pulls out a deployment bag, allowing the parachute inside to inflate automatically. Comprehensive jump course/accelerated free fall After hours of instruction, you’ll do your first jump with two instructors, who hold on to you to ensure you maintain a safe free-fall position – and that you pull your chute.…

DJI Osmo Action More features and better stabilisation than the GoPro Hero 7 Black. R6 999 myistore.co.za Instant Pot Pressure- and slow cooker, rice maker, steamer, sauté pan, warmer and yoghurt maker, all in one. From R1 999 takealot.com Ledlenser M11 Control settings with your smartphone. Rechargeable. Up to 1 000 lm brightness. R2 499 awesometools.co.za Manfrotto PIXI Lightweight. Perfect for travelling and holding compact cameras. R399 myistore.co.za Huawei FreeLace buds In-ear necklace-style wireless buds. Four hours’ playback on a five-minute charge. No pricing as yet. huaweistore.co.za Apple TV App Subscribe to Apple TV channels; download content. Pay for what you want. Available in iOS 12.3 and tvOS 12.3.…

CARRY YOUR OWN STRAW There are various other kinds of straws to choose from that reduce the impact on our planet. Thanks to their portability, silicone and metal straws can be taken wherever you go, while paper and bamboo straws serve as an eco-friendly alternative for cocktailor children’s parties. REUSE OR AVOID PLASTIC SHOPPING BAGS Since a levy was introduced in 2004, sales of plastic bags have been on a downward trend. Some major retailers are doing their part to get rid of them, but all it takes is for you to keep the ones you have and reuse them. Or, acquire an environmentally friendly option, made of canvas or cotton. RECYCLE As per recycling regulation, plastic products carry a logo with a numerical reference detailing the kind of plastic…

Melissa Beck, 38, welding student The photo subjects in this story are all students at Harrisburg Area Community College’s York Campus. Founded in 1964, when the surrounding suburbs were farmland, HACC is the oldest community college in Pennsylvania in the US, and serves 19 000 credit-seeking students and 6 000 students in non-credit programmes. Aside from the building and mechanical trades, you can learn CNC machining, brewing science (since May this year), and information technology at HACC. Thanks to the students, instructors, and administrators for welcoming us on a busy school day. Want a job? THE DEMAND FOR most trades, in most parts of the world, is strong and getting stronger. In the US, the Department of Labor forecasts healthy growth – in the neighbourhood of 8 to 9 per…

• Allowing the hot sauce to age over a couple of weeks helps with flavour development. • You can use bird’s-eye chillies to make the sauce very hot, but there are milder chillies for a slightly milder heat. You can also remove the seeds and pith from most, or half of the chillies, if you would like to make a milder sauce. • You can make a large batch of the sauce and keep one jar of it in the freezer. It defrosts perfectly and the vibrant colour remains. • Charring the chillies, peppers and tomato imparts a wonderful smokiness to the flesh. • Once charred, covering the charred chillies, tomatoes and peppers with cling film makes it a lot easier to remove the skins. • If your sauce is…

FLATTENING ANY wood that is too big for your jointer and thicknesser is a daunting task, but those large waney-edge slabs of exquisitely figured timber are just waiting for you to turn them into magnificent coffee-, boardroom-, couch-and dining tables. You can do this easily with your own cradle jig, or, like a growing band of enthusiasts, you can enjoy going off-grid with your scrub planes, jointer and fore planes, jack planes, smoothers and cabinet scrapers, saving you a fortune on gym fees. But what do you do with the cracks that inevitably come with large slabs of figured timber? How do you get the slab flat enough to finish it beautifully, and what do you need to achieve your dream waney-edged table? Slab work is actually extremely easy, although…

IF YOU WANT unpainted balusters, or balusters of a different colour than the rest of the trim on a railing, the rise of stairs can make it difficult to tape off a sharp line. Here’s a solution, courtesy of reader Brian Flynn: Cut a length of masking or painter’s tape roughly as long as the circumference of the baluster. Wrap it around the baluster, adhesive side out, then slide it to the top or bottom. The tape should be thin enough to slide into the gap where the baluster enters the handrail or bottom rail, and because its smooth side is against the surface, it’ll be easy to slide out when painting is complete. DEPTH GAUGE ON GARDEN TROWEL Up your efficiency when planting this year’s garden by filing depth…

ALL THIS TALK of autonomous cars of the future is well and good, and the world’s geeks are no doubt loving it because instead of playing World of Warcraft all day, they’re now employed by wealthy car companies to play with big radio-controlled cars. But let’s be brutally honest for just a moment: Computer whizz-kids probably got that way because they were never any good with people, and preferred the company of their laptops. I’d proffer that nowadays, very few have so much as driven a car – it’s difficult to find the time to get your learner’s licence when you play computer games for 18 hours a day, and hailing an Uber is just a thumb touch away. My point is, I simply do not think we’ve thought this…

Master Lock Small Security Chest: The continuous jamb and waterproof seal completely insulate contents from water. Ideal for protecting valuables from fire and water damage. Resistant to fire for half an hour, up to 840°C. Master Lock Spin Dial Combination Lock: Anti-shim technology withstands attempts to tamper with the latch mechanism. Features a 48 mm-wide double-reinforced stainless-steel body, 22 mm-tall hardened shackle, and a 3-number dialing combination lock. Master Lock Keyed Locking Cable: The 1.8 m long, 10 mm diameter braided-steel cable is designed for maximum strength. The vinyl coating prevents scratches, and protects the cable. The keyed lock is designed to resist picking. Carries a lifetime warranty. Send your tips to popularmechanics@ramsaymedia.co.za with the subject line: ‘Do It Your Way’. Regrettably, only South African residents are eligible for the…

The project area is affected by a strongly developed north-east trend of nearly vertical geological faults, which can be easily seen on aerial photographs. The Deka Fault appears to be the major tectonic feature of the region, and it’s likely responsible for the tilting of at least part of the basalt flows. Immediately upstream of the dam axis, the Zambezi River makes a sharp turn, which is controlled by a south-east trending lineament. The dam site is located at the beginning of a straight section of the river. Basalt outcrops cover both abutments with the overlying layer being less than five metres thick. It’s made up of blocky and gravelly talus material. Exposed in the riverbed are basalt outcrops, and there are no alluvial deposits at or around the site.…

RECENTLY, MY regular walk on the Sea Point Promenade has begun to feel a bit like The Jetsons. Between the electric bicycles, the motorised scooters and the self-balancing unicycles, there’s something whirring, whizzing or zooming everywhere I look. I’ve slowly moved from annoyance (‘Who are all these youngsters with their silly toys?’) to intrigue, and possibly jealousy (‘Actually, that looks really fun!’). I’m not the only one ambivalent about the new generation of catchily named ‘electric personal transportation devices’ or ‘e-mobility devices’. Cities across the world are being forced to consider the legalities (Do they count as pedestrians, bicycles or motor vehicles?) as e-scooters and e-bikes take over their pavements. World-wide sales of e-bikes hit 36 million units in 2016 and, last year, more electric than traditional pedal bicycles were…

(5) I was in Special Forces – a Green Beret, but I’m retired now. In Special Forces, we go into areas and we train and advise the host country’s forces. I’ve done that all over the world. So when we were in Afghanistan, a big part of that training cycle was medical. We had a lot of problems with the tourniquet we were being issued. We were very night-biased in how we worked – you know: night-vision goggles; we wore gloves, dark uniforms. The tourniquet that was issued was black. You had to feed some stuff through a little buckle, and it was very difficult to use in the dark and, most importantly, under stress. (6) Then I rotated back to the States, where I’d end up training other military…

LAST YEAR, I installed a large potjie-pot fireplace to warm our family room. The all-round radiant heat from this attractive fireplace was most welcome once the winter chill arrived. Then the first big cold front hit our area, accompanied by gale-force winds, which blew all the smoke and ash back down the flue and into the room. Turns out the cyclone-type flue cap was fine on calm nights or in a gentle breeze, but totally inadequate in high winds. We needed a directional flue hood. A bit of research revealed directional flue hoods range in price from about R900 to R1 500 – money I didn’t feel like spending – so I resolved to make one myself, using a piece of galvanised sheet metal I bought from our local engineering…

Follow these steps to flatten a slab: 1. Position the upper cradle at the extreme end of the slab, with the plunge router set to cut about 4–5 mm in a pass. 2. Clamp the upper cradle in position. 3. Router the first pass, making sure to cut the full width of the slab. 4. Loosen the clamps, then move the upper cradle over into the next cutting position, overlapping the previous cut by 5–10 mm. 5. Clamp the cradle and make the pass. 6. Continue in this way until you’ve cut the entire slab.…

RINGS Imagining the roots as the north pole of an onion globe, make a series of cuts parallel to the equator. SLICES Cut the onion in half through the roots (perpendicular to the equator). Taking each half in turn, place the flat side down, cut off the roots, then make a series of parallel north-south cuts. DICE Combine the slice- and ring techniques: Cut in half through the roots, then – keeping the roots on this time, to hold everything together – make parallel north-south cuts. Finish by cutting parallel to the equator, like you did for rings. The onion comes apart as dice. All the Stars Kendrick Lamar & SZA Bofou Safou Amadou & Mariam Some Birds Jeff Tweedy Them Changes Carlos Santana & Buddy Miles…

SQUEAKY CLEAN I’d like to share what I’ve found to be the best way to clean a pair of spectacles. For many years, I have been doing it wrong, using hand soap, and drying them off with a towel, or even using paper towels. All this kind of treatment does is damage the lenses and coatings, leaving behind many, many permanent scratches. After a lot of trial and error, I’ve discovered that the best way is to make a mild solution of Sunlight liquid (a drop or two will do) in a spray bottle with water. Shake the solution just a little and you’re good to go. This solution is mild enough to not damage the coatings on your lenses. I’ve found that hand soaps often leave behind residue, and…