This Is The Bike You Wanted Your Dad To Make You When You Were Eight Years Old!

November 16, 2019 by Jenny List 22 Comments

The ever-resourceful [Turbo Conquering Mega Eagle] has an excellent excuse for starting on projects, he’s building them for his kids and making videos. We’re not so sure his little motorcycle wasn’t built because Dad also wants to have a go though, because it seems he had quite a lot of fun testing it.

The build starts with a Chinese petrol conversion kit for a bicycle. There’s a little ~~two~~four-stroke motor and a basic chain drive to a large sprocket intended to fit on the opposite side of a bicycle wheel to the pedal sprocket. He uses a pair of pneumatic wheelbarrow wheels for which he makes a new bush and to which he welds the sprocket. These go into a fairly simple hardtail frame for which he makes a padded motorcycle seat, and from then on he’s ready to go.

The result is a rather cool little non-road-legal motorcycle that we suspect most readers will have a hankering to own. We’re not so sure about its seeming lack of brakes though. Judge for yourself, the video is below the break.

This isn’t the first home made small bike we’ve brought you, though it’s a lot safer than the first one.

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Bicycle Transforms Mid-Ride

November 13, 2019 by Bryan Cockfield 9 Comments

For those of us who were children in the late 80s and early 90s, we may have dreamed of one day owning a gigantic tractor trailer that could transform into a colossal fighting robot. Or of simply having a toy that could approximate this change from one form into another. As adults, though, we have come to realize that this is wishful thinking. That is, unless we decide to build this transforming bicycle.

What starts out as a slightly unusual-looking low rider-style bike effortlessly turns into a tall bike by means of a gas cylinder fixed to the bike’s rear triangle. The bike started out as a full suspension mountain bike, but the rear spring was removed to make room for this cylinder. The pivoting action of the rear triangle in a mountain bike is the key design element here: it allows the frame to change shape easily, in this situation when pushed by the cylinder. Adding some longer forks in the front and a coat of paint finishes the build.

This bike was entered in the Make It Move contest on Instrucables, and has gotten some pretty wide recognition so far. It’s a unique bicycle to be sure, and we’ve seen a few. From Russian offroad electric utility bicycles to bicycles that keep drivers from speeding down roads, there have been lots of interesting bike-based builds.

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Cardboard Longboard Uses Quarter-Isogrid Structure

November 12, 2019 by Lewin Day 19 Comments

Skateboards are most typically crafted by hand, carved out of wood layered by care. However, many makers have sought to explore alternative techniques. [Technovation] decided to combine alternative materials and digital fabrication techniques to produce this attractive cardboard longboard.

The structure of the board was designed in Fusion 360, featuring a quarter isogrid design. The structure consists of stringers connected by ribs, all made of cardboard, with interlocking slots to hold everything together. 1/4″ plywood is then used to reinforce the truck mounts, and a top and bottom baseplate of 4mm acrylic is installed to protect the cardboard from damage.

The parts for the board are all laser cut, making production and assembly a snap. No glue is used, either – the structure is able to hold itself together perfectly well with its slotted construction. The team note that having a rider on the board does create some significant flex, but it hasn’t caused a failure in practice.

Skateboards are a popular maker project, and we’ve seen all kinds over the years. Modern manufacturing techniques are often brought to bear, or designs are created to solve tricky travel problems. Video after the break.

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The Rotodyne Fails To Take Off

November 9, 2019 by Al Williams 45 Comments

Bacon and eggs, chocolate and peanut butter, salt and pepper; some things just go together. You’d think that a mashup of an airplane and a helicopter would be great, right? The Fairey Rotodyne was just such a thing from the late 1950s and while it looked to be the wave of the future, it never took off — at least, not in the business sense at least. [Mustard] has an excellent video about the machine including some flight footage and explains why it failed to take over the aviation market. You can watch the video below.

While it does look like a helicopter mated with an airplane, it’s actually a bit different. The rotor isn’t normally powered at all. However, it does turn in forward flight and generates about half the lift the plane needs. That explains the stubby wings. The topside rotor has small jets at the tips that can be used during vertical take off, landing, and hovering modes.

For its time, it was fast and efficient, especially compared to contemporary helicopters. This type of plane was known as an autogyro and actually appeared in the 1930s as a safety mechanism since an autogyro can land in an autorotation mode.

According to the video, the noisy tip jets and production delays killed the beast. There was only one prototype built, but there was something we found very attractive about it. There have been, of course, other autogyros. British, German, Japanese, and Russian military have used autogyros at one time or another. The United States Postal Service was known to employ at least one.

Even today, there are about a thousand autogyros used by different military and police organizations. They are cheaper than a helicopter to buy and fly. Sadly, though, it doesn’t look like autogyros will ever become a common sight. Like an airship, they seem like a callback to an earlier time when you have a chance to spot one.

We are always surprised we don’t see more model autogyros. We wonder how they’d be at cutting down trees.

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Autonomous Air Boat Vs Lake Washington

November 6, 2019 by Danie Conradie 9 Comments

Autonomous vehicles make a regular appearance around here, as does [Daniel Riley] aka [rctestflight]. His fascination with building long-endurance autonomous vehicles continues, and this time he built an autonomous air boat.

This craft incorporates a lot of the lessons learnt from his autonomous boat that used a plastic food container. One of the biggest issues was the submerged propellers kept getting tangled in weeds. This led [Daniel] to move his props above water, sacrificing some efficiency for reliability, and turning it into an air boat. The boat itself is catamaran design with separate 3D printed hulls connected by carbon fibre tubes. As with the tupperware boat, autonomous control is done by the open source Ardupilot software.

During testing [Daniel] had another run in with his old arch-nemesis, seaweed. It turns out the sharp vertical bow is a nice edge for weeds to hook on to, create drag, and screw up the craft’s control. [Daniel]’s workaround involved moving the big batteries to the rear, causing the bows lift almost completely out of the water.

With a long endurance in mind right from the start of the project, [Daniel] put it to the test with a 13 km mission on Lake Washington very early one morning. For most of the mission the boat was completely on its own, with [Daniel] stopping at various points along the lake shore to check on its progress. Everything went smoothly until 10 km into the mission when the telemetry showed it slowing down and angling off course, after which is started going in circles. Lucky for Daniel he was offered a kayak by a lakeside resident, and he managed to recover the half sunken vessel. He suspects the cause of the failure was a slowly leaking hull. [Daniel] is already working on the next version, and were looking forward to seeing what he comes up with. Check out the video after the break. Continue reading “Autonomous Air Boat Vs Lake Washington” →

Traffic Updates On The Seven Seas: Open Source Chart Plotter Using A Raspberry Pi

November 4, 2019 by Danie Conradie 7 Comments

As the Raspberry Pi in its various forms continues to flow into the wild by the thousands, it’s interesting to see its user base expand outside beyond the hacker communities. One group of people who’ve also started taking a liking to it is sailing enthusiasts. [James Conger] is one such sailor, and he built his own AIS enabled chart plotter for a fraction of the price of comparable commercial units.

AIS transponders in the Mediterranean. VesselFinder

Automatic Identification System (AIS) is a GPS tracking system that uses transponders to transmit a ship’s position data to other ships or receiver stations in an area. This is used for collision avoidance and by authorities (and hobbyists) to keep an eye on shipping traffic, and allow for stricken vessels to be found easily. [James]’ DIY chart plotter overlays the received AIS data over marine charts on a nice big display. A Raspberry Pi 3B+, AIS Receiver Hat, USB GPS dongle and a makes up the core of the system. The entire setup cost about $350. The Pi runs OpenCPN, an open source chart plotter and navigation software package that [John] says is rivals most commercial software. As most Pi users will know the SD card is often a weak link, so it’s probably worth having a backup SD card with all the software already installed just in case it fails during a voyage.

We’ve seen AIS receiver stations built using the RTL-SDR, as well as a number of projects around the AIS equivalent in aviation, ADS-B. Check out [John]’s video after the break. Continue reading “Traffic Updates On The Seven Seas: Open Source Chart Plotter Using A Raspberry Pi” →

Massive 3D-Printed Ridable Tank Boggles The Mind

November 2, 2019 by Danie Conradie 19 Comments

Anyone who has used an FDM 3D printer knows just how long the process can take, especially when you really start filling up the available print volume. Apparently [Ivan Miranda] has absolutely zero fear of insanely long print times, and is in the process of building a massive ridable tank (YouTube playlist of the whole build) that is almost completely 3D printed.

[Ivan] is no stranger to large prints, but this tank is on a different level altogether. The chassis, which is reinforced with aluminium and steel square tubing, took around 1200 hours to print and each of the wheels took 6 days! The rolling chassis with wheels and track weighs close to a 100 kg. Having built a few smaller 3D printed tracked vehicles before, [Ivan] used a lot of that knowledge to design the latest monster.

Connecting the tracked section together has always proven challenging for [Ivan]. This time he used plastic fish tape (wire puller) for the pins, and blocked off the end holes with screws. The bogies (wheel sets) are also interesting, with 3D printed springs that sit parallel to the ground. Almost all the parts are printed in PLA, which can be quite brittle, so it would be interesting to see how it holds up.

[Ivan] has been working on this project since the start of 2019, and we can’t wait to see it completed. We’ve featured his signature red prints a few times, including a RC car that drives on the ceiling and a water jet drive. If you’re keen to build your own tank on the opposite side of the size spectrum, check out this tiny tank for your crawl space. Watch [Ivan] finish the rolling chassis after the break. Continue reading “Massive 3D-Printed Ridable Tank Boggles The Mind” →