Turbocharger Jet Engine Relies On Wood Pellet Ignition

December 22, 2021 by 14 Comments

Turbochargers as used on cars bear some similarities with jet engines. Fundamentally, both contain a turbine that harvests energy from hot gas, using it to spin a compressor which sucks in fresh air for combustion. Thus, turning a turbocharger into a jet engine is entirely possible, and [HRom] decided to have a crack at it. 

The build starts with a turbo that appears to have been used on a diesel engine from the Volkswagen group. The first step was to cut the integral exhaust manifold off the turbo housing. A combustion chamber is then added which takes in fresh air from the compressor housing, and delivers hot combustion products to the turbine inlet. The homebrewed jet engine burns propane as fuel, introduced into the chamber via a nozzle.

The initial test failed as combustion was occurring at the turbine exhaust rather than in the combustion chamber, likely due to the lack of a proper ignition source inside the combustion chamber. A redesign employed a bigger combustion chamber built out of a fire extinguisher, with smouldering wood pellets inserted inside to get the injected propane burning.

The redesign works, and the turbocharger jet engine releases a thunderous scream as it turns at ever-increasing speed. However, with no oiling system or any way of controlling air or fuel flow in the engine, it eventually stops in a huge puff of smoke. Regardless, the engine did run in a sustained manner even if the ignition method was rudimentary.

We’ve seen similar builds before, and the rudimentary construction means they’re typically nowhere near being flight-weight engines. They are incredibly cool, however, and a great way to learn the basic principles of how jet engines work. Video after the break.

Continue reading “Turbocharger Jet Engine Relies On Wood Pellet Ignition” →

How To Forge A Skillet From Scratch

December 22, 2021 by 11 Comments

Cookware isn’t something we typically build ourselves; you’d want a well-equipped metal shop to do the job and do it right. [Torbjörn Åhman] has just that, however, and set about forging a stout-looking skillet from scratch.

The build starts with a round disc of steel serving as a blank for the project. The blank is spun up and the outer perimeter ground down thinner with an angle grinder in what looks like a moderately sketchy operation. A forge is then used to heat the blank so that it can be shaped into a pan using a hammer. Slowly, as the metal is beaten one way and then t’other, the skillet begins to form. A belt sander takes off high points on the outside, and a torch is then used to square up the base of the pan so it sits nicely. Finally a handle attached with some stout rivets, and the newly formed piece of cookware gets a seasoning with sunflower oil.

The project shows just how many special skills are required to make even simple cookware by hand. It’s nice to see some keeping the old methods alive, too. Video after the break.

Continue reading “How To Forge A Skillet From Scratch” →

Tech In Plain Sight: Primitive Engineering Materials

December 22, 2021 by 33 Comments

It isn’t an uncommon science fiction trope for our hero to be in a situation where there is no technology. Maybe she’s back in the past or on a faraway planet. The Professor from Gilligan’s Island comes to mind, too. I’d bet the average Hacakday reader could do pretty well in that kind of situation, but there’s one thing that’s often overlooked: materials. Sure, you can build a radio. But can you make wire? Or metal plates for a capacitor? Or a speaker? We tend to overlook how many abstractions we use when we build. Even turning trees into lumber isn’t a totally obvious process.

People are by their very nature always looking for ways to use the things around them. Even 300,000 years ago, people would find rocks and use them as tools. It wasn’t long before they found that some rocks could shape other rocks to form useful shapes like axes. But the age of engineered materials is much younger. Whether clay, metal, glass, or more obviously plastics, these materials are significantly more useful than rocks tied to sticks, but making them in the first place is an engineering story all on its own.

Continue reading “Tech In Plain Sight: Primitive Engineering Materials” →

Solder stencil vacuu assist jig

Stencil Vacuum-Assist Helps Avoid The Heartbreak Of Smeared Solder Paste

December 22, 2021 by 9 Comments

While using a stencil should make solder paste application onto PCBs a simple affair, there are a number of “gotchas” that make it more art than science. Luckily, there are tools you can build, like this 3D-printed vacuum-assist stencil jig, that take a little of the finesse out of the process.

For those who haven’t had the pleasure, solder paste stencils are often used to make the job of applying just the right amount of solder paste onto the pads of a PCB, and only on the pads. The problem is that once the solder paste has been squeegeed through the holes in the stencil, it’s not easy to remove the stencil without smearing. [Marius Heier]’s stencil box is essentially a chamber that attaches to a shop vac, along with a two-piece perforated work surface. The center part of the top platform is fixed, while the outer section moves up and down on 3D-printed springs.

In use, the PCB is placed on the center fixed platform, while the stencil sits atop it. Suction pulls the stencil firmly down onto the PCB and holds it there while the solder paste is applied. Releasing the suction causes the outer section of the platform to spring up vertically, resulting in nice, neat solder-covered pads. [Marius] demonstrates the box in the video below, and shows a number of adapters that would make it work with different sized PCBs.

If you think you’ve seen a manual vacuum stencil box around here recently, you’re right — we featured one by [UnexpectedMaker] not too long ago.

Continue reading “Stencil Vacuum-Assist Helps Avoid The Heartbreak Of Smeared Solder Paste” →

The Dreamcast Legacy

December 22, 2021 by 48 Comments

The Dreamcast is a bit of an odd beast. Coming on the heels of the unpopular Sega Saturn, the Dreamcast was meant to be a simple console built with off-the-shelf parts and released in late 1998. The Nintendo 64 was already tough competition (1996). Ultimately, the Dreamcast fell out of the public eye in the early 2000s as the Playstation 2, Xbox, and Gamecube were all released with incredible fanfare just a few years later. In some sense, Sega’s last console is a footnote in gaming history.

But despite not achieving the success that Sega hoped for, the Dreamcast has formed a small cult following, because as we know, nothing builds a cult-like following like an untimely demise. Since its release, it has gained a reputation for being ahead of its time. It was the first console to include a modem for network play and an easy storage solution for transferring game data between consoles via the VMUs that docked in the controllers. It had innovative and classic games such as Crazy Taxi, Jet Set Radio, Phantasy Star Online, and Shenmue. Microsoft even released a version of Windows CE with DirectX allowing developers to port PC games to the console quickly.

We see our fair share of console hacks here on Hackaday, but what is the ultimate legacy of the Dreamcast? How did it come to be? What happened to it, and why did so much of Sega’s hopes ride on it? Continue reading “The Dreamcast Legacy” →

You Can 3D Print A Working Reciprocating Steam Engine

December 22, 2021 by 12 Comments

3D prints aren’t typically known for their heat resistance. However, [Integza] noted that using the right techniques, it was possible to 3D print parts that could handle steam heat without failing. Thus, the natural progression from there was to build a piston-type steam engine.

The sliding valve alternately feeds steam to each side of the piston.

Resin prints are key here, as the melting point of such parts is much higher than that of those turned out by typical FDM printers. Try this same build using PLA for the hot parts, and you’ll quickly end up with a pile of molten goo.

To make such an engine work, valves are required to allow steam to flow into alternating sides of the piston to let it reciprocate continuously. A simple slide valve is used, allowing steam to flow to one side of the piston and the other alternately, as driven by an arm coming off the flywheel attached to the engine’s output shaft.

Tested on compressed air and steam, the engine ran continuously, chugging away enthusiastically. However, steam performance was compromised by the low pressure output of just 1.5 bar from [Integza]’s pressure cooker. Similarly, the cooker’s steam capacity was low, so the engine ran for just 15 seconds.

However, it suggests that with a better supply of steam, the printed steamer could indeed run for some time. If you’re not into the wetter engines out there, though, consider extruding a Stirling engine instead. Video after the break.

Continue reading “You Can 3D Print A Working Reciprocating Steam Engine” →

Linux For The Paranoid Does The Work For You

December 22, 2021 by 42 Comments

We all know that our activity on the Internet is not that hard to track. It just annoys some people more than others. If you are really hardcore, you’ll learn all the ins and outs of networking to help cover your tracks, but what if you don’t want to invest that kind of time? Maybe, as [TechRepublic] suggests, try Kodachi Linux.

You could, of course, start with your own live image. Then when you boot, you could take the following steps:

  • Randomize your MAC Address
  • Establish a TOR connection through a VPN
  • Route all internet traffic through TOR and use DNS encryption
  • Set up a scheduled task to scramble your MAC address periodically

But that’s what Kodachi does without any real effort on your part.

The distribution is based on Ubuntu, so all the familiar tools are there. There are also a few security and privacy tools included like KeePass, Tox, OnionShare, i2p, and more. The desktop shows a summary of secure network information

Do you need Kodachi? Probably not, if you are a Linux guru. Plus, most people aren’t doing anything that’s that interesting. But if you want to protect your privacy or you are up to something, give Kodachi a try. Then again, if you are that paranoid, maybe that’s just what THEY want you to do. Make your own decisions. You can also check out the video review from [eBuzz Central] below.

Looking for more conventional Linux? Why not Rocky Linux? If you just want a VPN, you can always just use ssh.

Continue reading “Linux For The Paranoid Does The Work For You” →