Retrotechtacular: London Bus Overhaul

If you have ever visited London as a tourist, what memories did you take away as iconic of the British capital city? The sound of Big Ben sounding the hour in the Elizabeth Tower of the Palace of Westminster perhaps, the Yeoman Warders at the Tower of London, or maybe the guardsmen at Buckingham Palace. Or how about the red double-decker buses? They’re something that, while not unique to the city, have certainly become part of its public image in a way that perhaps the public transport of other capitals hasn’t.

A city the size of London has many thousands of buses in the fleet required to provide transport to its sprawling suburbs. Until a few years ago the majority of these machines were built to a series of standard designs under the London Transport banner, so a Londoner with an eye for buses could have seen near-identical vehicles in any corner of the city. Each of these buses would have carried millions of passengers over hundreds of thousands of miles in a typical year, so many in fact that every few years they would have required a complete overhaul. For that task, London Transport maintained a dedicated factory capable of overhauling hundreds of buses simultaneously, and this factory is our subject today.

The overhaul works at Aldenham was the subject of a 1957 British Transport Films picture, Overhaul, in which we follow a bus in its journey through the system from tired-out to brand-new. We see the bus given a thorough inspection before being stripped of its upholstery and then having its body separated from its chassis and cleaned, then we see each part being refurbished. Along the way we gain a fascinating insight into the construction of a mid-century passenger transport vehicle, with its wooden frame and aluminium exterior panels being refurbished and rebuilt where necessary, before the camera. Meanwhile we see the chassis, with its separate gearbox in the centre of the vehicle, before it is painted to resist more years of road grime and reunited with a bus body. The completed vehicle is then taken for a test run before being sent to the paint shop for a coat of that iconic London Transport red. Enjoy the film in its entirety below the break.

The buses in the film are the AEC/London Transport “RT” vehicles, which entered service in the late 1930s and last ran in the 1970s. Their replacement, the visually similar “Routemaster” had only started to appear the previous year, and continued in regular service until 2005. Meanwhile the Aldenham bus overhaul works survived until its closure in 1986 due to the appearance of a range of new buses in the capital that did not conform to the standard design that it had been designed to serve.

Continue reading “Retrotechtacular: London Bus Overhaul”

Our Gunpowder And Tea Came From China, Why Didn’t We Copy Their Wheelbarrows?

My dad's low-loader barrow. You would not believe how useful it is.
My dad’s low-loader barrow. You would not believe how useful it is.

Everyone must have a few things that are emotive of their childhood, perhaps a sight, a sound, or a smell. For me, growing up as I did on a small British organic farm in the 1970s, my emotive things are the smell of rain hitting parched earth, or of the slightly sulphurous diesel exhaust from a clapped-out Fordson Major tractor. And wheelbarrows, strangely. My dad, you see, is both a blacksmith by trade and an inveterate experimenter in the field of handcarts and barrows. A small self-sufficient farm generates a huge range of different loads that need carrying around, and he fashioned a variety of inventive contraptions for the purpose. Of most use are his oversized builder’s barrows with a full-size van wheel at the front and able to cross the bumpiest of ground, but other highlights included the low-loading barrow for shifting the heaviest one-piece loads, or the two-wheeler for very long objects.

As you might expect then, I have an eye for a barrow, as I’ve pushed a few in my time. So when I read about how traditional Chinese barrows are constructed, they caught my attention and I had to ask: why don’t we do it that way?

Continue reading “Our Gunpowder And Tea Came From China, Why Didn’t We Copy Their Wheelbarrows?”

Take A Look At The Hyperloop Competition Entries

If you are a follower of futuristic high-speed transport systems you’ll have had your fill of high-speed trains, you’ll mourn the passing of Concorde and be looking forward to future supersonic passenger aircraft. Unless you have a small fortune to pay for a spaceplane tourist flight at an unspecified time in the future, life is going to feel a little slow.

There is one spark of light in this relative gloom though, in the form of Elon Musk’s Hyperloop. A partially evacuated tube in which vehicles, or “pods” can accelerate to very high speeds. SpaceX may not be pursuing it themselves, but they’ve made it available for others and to promote it they are running a competition in which they have invited teams to submit pod designs. And as a significant number of teams have made it through the first round and are prepared to compete outside SpaceX’s headquarters, Business Insider have a look at all the teams and their prototype pods. Continue reading “Take A Look At The Hyperloop Competition Entries”

Half a Chevy Becomes a Boat Launch

A tired 1990 Chevy Lumina isn’t the platform one would normally pick for a custom build. When you’re drag boat racing team on a budget though, you use what you can get cheap. Normally small boats are launched and landed using a trailer and tow vehicle. [Ashley Ruf’s] team at Little John’s racing is launching her boat “Kwitchabitchin” with a bit more style.

The team started by cutting the Lumina in half. Since the Chevy is a front wheel drive platform, everything behind the driver is more or less along for the ride. The gas tank was relocated, and notched to receive the front of the boat. The team then added a quad tire trailer frame. The frame is connected to the car with a long hydraulic cylinder. When the boat is being launched or landed, the cylinder can extend far enough to get the boat floating.

You might be thinking that there is no way this is street legal, and you’d be right. The Lumina only gets the boat into and out of the water. The boat is then pulled all the way forward using the hydraulics. The boat/car pair is a then perfect fit inside the team’s racing travel trailer.

You can check out a video of the car at work after the break

Continue reading “Half a Chevy Becomes a Boat Launch”

Converting an Electric Scooter to Lithium Batteries and Disabling the Safeties

There’s a bunch of different electric scooters available nowadays, including those hoverboards that keep catching fire. [TK] had an older Razor E300 that uses lead acid batteries. After getting tired of the low speeds and 12 hour charge times, [TK] decided it was time to swap for lithium batteries.

The new batteries were sourced from a Ryobi drill. Each provides 18 V, giving 36 V in series. The original batteries only ran at 24 V, which caused some issues with the motor controller. It refused to start up with the higher voltage. The solution: disable the safety shutdown relay on the motor controller by bridging it with a wire.

With the voltage issue sorted out, it was time for the current limit to be modified. This motor controller uses a TI TL494 to generate the PWM waveforms that drive a MOSFET to provide variable power to the motor. Cutting the trace to the TL494’s current sense pin removed the current limit all together.

We’re not saying it’s advisable to disable all current and voltage limits on your scooter, but it seems to be working out for [TK]. The $200 scooter now does 28 km/h, up from 22 km/h and charges much faster. With gearing mods, he’s hoping to eke out some more performance.

After the break, the full conversion video.

Continue reading “Converting an Electric Scooter to Lithium Batteries and Disabling the Safeties”

Press Amazon Dash Button, Summon Uber

Modern life is complicated. When you want to call an Uber car to pick you up, you have to open the app, sign in and set your pickup location. [Geoffrey Tisserand] uses Uber to commute to his job in San Francisco every day, so he came up with a neat way to automate this process, by reprogramming an Amazon Dash button to call an Uber. All he has to do is to hit the button, and a few minutes later an Uber rolls up to his door.

To do this, he used the intercept method, where a Python script running on another computer notices the Amazon Dash button joining his home WiFi network and posts the request to Uber. Because Uber uses the OAuth authentication system, he was able to easily log into the system using Expressjs. And because he is always following the same route, he could also automate the posting of the pickup and dropoff locations, as they don’t change. It’s a neat hack that saves him time, but it doesn’t get around the issue of letting you know how long the car will take to arrive, or if Uber is in Surge Pricing. Perhaps that would work for version 2: a small button with an LCD screen and a warning light.