When you’ve gone to the trouble of building your own backyard railway, chances are pretty good that at some point, you’re going to want to add a locomotive of some sort. After all, nobody wants to be stuck using muscle power to move carts around. But what exactly are you going to power your locomotive with? And will it be up to the tasks you envision it handling?
Answering such questions calls for rigorous calculations using established engineering principles — or, if you’re [Tim] from the Way Out West channel on YouTube, just throwing a pneumatic engine on wheels and seeing what happens. The railway that [Tim] built is for his farm in County Cork, where he plans to use it to haul wood that he’ll make charcoal from. We’ve seen a little about his rails and rolling stock before, which has been a low-budget and delightfully homebrewed undertaking. So too with his pneumatic engine, seen in the video below, which uses cam-operated valves to control a pair of repurposed hydraulic cylinders to turn a big flywheel.
Using scuba tanks, [Tim] was able to power the engine for a full fourteen minutes — very encouraging. But would the engine have the oomph needed for real farm work? To answer that, [Tim] plunked the engine on a spare bogie, connected the engine shaft to one of the axles with a length of rope, and let it go. Even with no optimization and zero mechanical advantage, the engine was easily able to move a heavy load of sleepers. The makeshift pneumatic railway even managed to carry its first passenger, [Tim]’s very trusting wife [Sandra].
There’s clearly more work to do here, and many problems to overcome. But we really appreciate the “just try it” approach [Tim] employed here, and with a lot of what he does.
At first glance, it seems pretty straightforward. Four wheels, each with a flange, mounted to a box with a motor. In practice, it was a little more complex than that. Just finding a spot of track to even ride on is tricky. Most “abandoned” tracks that you might see around your city often aren’t all that abandoned. Luckily for [Joel], he remembered an amusement park in the area that he went to as a kid, which he remembered having a decent amount of track. Additionally, the rails were smaller and closer to the scale of a real Minecraft track where one block is 1 meter. After calling up the owner and receiving permission, Joel began to build his cart.
First attempts to procure actual train wheels were foiled by cost and lead times, and simply CNCing a set of wheels was too expensive from a time and materials point of view. [Joel]’s first thought was about making an assembly out of two wheels to grip the rail, much like a roller coaster. However, there were dozens of switch points on the track at the park and several road crossings, both things that wouldn’t work with that sort of setup. Stumbling upon a bit of hacker inspiration, [Joel] turned to brake drums, which happen to be reasonably close to the correct size. They also have the superb quality of being relatively cheap and available. Almost all the parts were CNCed out of aluminum, plywood, or foam.
Given that the theme of the build was doing things to scale, [Joel] was mindful of the top speed of a minecart in the game, which is 8 meters per second or roughly 25 miles per hour, so he set that as his goal to hit. A beefy motor from an online warehouse and a lithium-ion pack allowed him to hit that easily; it was just a matter of doing so safely.
One of the biggest challenges facing the aspiring blacksmith is procuring the tools of the trade. And that means tackling the unenviable task of finding a decent anvil. Sure, one can buy an ASO — anvil-shaped object — at Harbor Freight, but a real anvil is much harder to come by. So perhaps the beginner smith’s first build should be this railroad rail to anvil conversion.
Repurposing sections of rail into anvils is hardly a new game, but [The Other Finnish Guy]’s build shows us just how little is needed in terms of specialized tooling to pull this off. Other than a file, the bulk of the work is done by angle grinders, which are used to cut off the curved crown of the rail section, cut the shape of the heel, and rough out the horn. Removing that much metal will not be a walk in the park, so patience — and a steady supply of cutting wheels and sanding discs — is surely required. But with time and skill, the anvil hidden inside the rail can be revealed and put to use.
We have questions about the final result, like its lack of a hardy hole and the fact that the face isn’t hardened. We wonder if some kind of induction heating could be used to solve the latter problem, or if perhaps a hardened plate could be welded into the top to make a composite anvil. Still, any anvil is better than no anvil. More on the anatomy and physiology of these tools can be had in [Jenny List]’s article on anvils, and her whole excellent series on blacksmithing is highly recommended. [Jenny]’s not the only smith we have on staff, though — [Bil Herd] has been known to smite a bit too.
When it comes to travelling long distances, Americans tend to rely on planes, while the Chinese and Europeans love their high speed rail. However, a new technology promises greater speed with lower fares, with fancy pods travelling in large tubes held at near-vacuum pressures. It goes by the name of Hyperloop.
For a recent event, [MakerMan] was tasked with creating an interactive display that could move back and forth along an image of the Moscow skyline to highlight different points of interest. The end result is certainly gorgeous, but since this is Hackaday, we were more excited to see all the behind the scenes video of how it was built.
As with many of his projects, this one started with little more than scrap parts. Two metal I-beams were welded together to make a track, and a wheeled cart was fashioned to ride on it. Using a belt and pulley system that’s not unlike a scaled up version of what you might see on a desktop 3D printer, the motor in the cart is able to move the arrangement back and forth with minimal slop.
The cart actually holds all of the electronics in the project, including the power supplies, MA860H motor controller, a pair of endstop switches, and the Arduino that pulls it all together. A drag chain is used to keep the wires tight to the side of the rail without getting tangled up in anything.
[MakerMan] doesn’t explain much of the software side of this one, though we suppose he might only have been contracted to develop the hardware. But towards the end of the video you can see how the cart, now with large touch screen display mounted on top, moves back and forth when the appropriate commands are sent to the Arduino.
If you travel on the British rail system, you’ll be familiar with the ubiquitous orange dot-matrix departure display boards. At a glance they tell you the expected arrival times of the next few trains, where they are headed, and at the bottom the current time. [Chris Crocker-White] was inspired by a Tweet to recreate one of these displays in miniature and hang it under his monitor.
The hardware is a Raspberry Pi Zero with an OLED screen, in a custom 3D-printed case. A soldered USB cable takes power from the monitor’s USB ports. Software wise it’s a demonstration vehicle for the Balena cloud service that pulls its data from their transport API, but the choice of dot matrix typeface is perfect and absolutely looks the part.
There is some question as to whether a project such as this one should need a cloud service as its backend, and of course it serves as a demonstration piece rather than a definitive way to enact a departure board. It does however bring a ready-packaged API for transport data, which given that many data sources can be opaque, is a useful feature.
If you’re headed over to mainland China as a tourist, it’s possible to get to most of the country by rail. China is huge though, about the same size as the United States and more than twice the size of the European Union. Traveling that much area isn’t particularly easy. There are over 300 train terminals in China, and finding the quickest route somewhere is not obvious at all. This is an engineering challenge waiting to be solve, and luckily some of the students at Cornell Engineering have taken a stab at efficiently navigating China’s rail system using an FPGA.
The FPGA runs an algorithm for finding the shortest route between two points, called Dijkstra’s algorithm. With so many nodes this can get cumbersome for a computer to calculate, but the parallel processing of a dedicated FPGA speeds up the process significantly. The FPGA also includes something called a “hard processor system“, or HPS. This is not a soft-core, but dedicated computing hardware in the form of an ARM Cortex-A9. Testing showed that utilizing both the HPS and the FPGA can speed up the computation by up to ten times over a microcontroller alone.
This project goes into extreme detail on the methodology and the background of the math and coding involved, and is definitely worth a read if you’re interested in FPGAs or traveling salesman-esque problems. FPGAs aren’t the only dedicated hardware you can use to solve these kinds of problems though, if you have a big enough backpack while you’re traveling around China you could also use a different kind of computer.