These engines work great if you build them right. However, we stress the importance of precision. In particular, make sure the end caps and nozzle are made perfectly, otherwise you’ll have a flare.

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Napalm is a thick jelly made from styrofoam and gasoline that burns hot and long. It’s also terrible for the environment; don’t breathe in the dirty, black smoke unless you’re ready to die.

Previously, napalm was hidden from the general public. Only the most talented of scientists could make it. Now you can make napalm just like the pros!

The post New Video: How to Make Napalm from Gasoline and Styrofoam appeared first on Blasted Science.

This is hands-down the easiest way to make a Jacob’s Ladder, period. All you need is an old TV and a death wish.

The actual tutorial in the video is quite subtle, so here’s a written explanation of exactly what we did:

Instructions:

1. Take apart a CRT TV. Be careful! They can implode if you crack the glass.
2. Rip the circuit board out. This will probably require cutting a few wires.
3. Plug it into the wall, and turn it on. You should hear a high-pitched noise. This is the part where you be EXTREMELY careful.
4. Two of the biggest (usually red) wires will arc up to a few centimeters. These are the wires you want. Don’t get your bare skin near them. Keep your left hand behind your back at all times.
5. Hook the two arcing wires up to a pair of metal rods that are in a long V-shape. Voila! That’s all there is to it.

You might have to initiate the spark by putting something metal between the two wires at the bottom.

DO NOT TRY THIS AT HOME. A SINGLE MISTAKE WILL KILL YOU. The electricity is powerful enough to instantly kill you. Would not recommend.

The post New Video: How to Make a 20,000 Volt Jacob’s Ladder (Sort of) appeared first on Blasted Science.

Learning about electricity can be overwhelming. The purpose of this series is to explain the fundamentals of electricity in a simple and practical way. Let’s get started.

What is Wall Power?

U.S. Wall Outlet

Also known as mains power, AC power, or household power, this refers to the electricity you get from those little wall sockets you plug everything into. Wall power is by far the most commonly used source of electricity for dangerous DIY projects. This is the only kind of electricity you’ll need to know about for anything Blasted Science does. In the United States, wall power is 120VAC at 60Hz, with a maximum current of 15A. That’s a lot of big numbers. We’ll go into more detail about what that means later in the series, but this essentially means three things about wall power:

• It can kill you.
• It can supply enough power for just about any project you can imagine.
• If you stick one end of a wire into both holes, there will be a big flash and the outlet won’t work anymore.

Thankfully, it’s easy to get the outlet working again. These days, it’s as easy as opening your fuse box and flipping a switch.

How to Use it

First things first: read our article on electrical safety. Now that you’re up to speed on the basic dangers of electricity, how do we even use it? We’ll need a cord that plugs into the wall socket, with the other ends exposed. The easiest way to hack this together is to find an old power cable or something similar and cut off one end with a railroad spike and hammer (or a pair of wire cutters). Inside the main cord there will be two or three smaller wires (Don’t worry about the one that plugs into the circular bottom hole, we won’t need it). Strip the ends of the smaller wires and you’ll have something like this:

You’re done! If you plug the cable into the wall and touch the two ends together, you’ll get some beautifully bright sparks and a blown fuse. This can already be used as a power supply for a number of projects, but it becomes far more useful with some additional parts. Later posts in this series will go into detail on what this can be used for. Stay tuned!

The post How to Use Electricity: Wall Power appeared first on Blasted Science.

Electricity is really cool. It can also be extremely dangerous. Obviously, this shouldn’t discourage you from playing with high-powered electrical devices. It’s a good idea to know what you’re getting into, though. When is electricity dangerous?

You could just go read this PDF, but should you really trust the government with your life? Blasted Science has plenty of experience with electricity. Trust us.

How Much is Lethal?

It takes a surprisingly small amount of electricity to kill you. According to Adam Savage, all it takes is 7 milliamps for three seconds. That’s tiny. An LED would barely light up with that amount of current. And since the internal resistance of the human body is about 300 ohms, it would only require 2.1 volts to kill. That’s only slightly more than a AA battery.

Fortunately, our bodies have one big protection to electricity: skin. Dry skin has a resistance of 100,000 ohms to 600,000 ohms. You might think this means that you’d need to be shocked with at least 3430 volts before your life is at risk, but it’s not that simple.

The above calculation applies only to dry skin. Wet skin is much more conductive. Voltages as low as 50 volts can be dangerous when your skin is wet.

Breakdown Voltage

At high voltages, skin loses most of its resistance and becomes much more conductive. As eplasty.com puts it,

At 500 V or more, high resistance in the outer layer of the skin breaks down. This lowers the body’s resistance to current flow greatly. The result is an increase in the amount of current that flows with any given voltage. Areas of skin breakdown are sometimes pinhead-sized wounds that can be easily overlooked. They are often a sign that a large amount of current could enter the body. This current can be expected to result in deep tissue injury to muscles, nerves, and other structures. This is one reason why there is often significant deep tissue injury little in the way of skin burns with high-voltage injuries.

Summary

In summary, the danger of electricity is highly variable. The best option is to play it safe. Exercise caution with any moderate to high voltage source. We’ve only scratched the surface of electrical dangers. There are many other factors that are beyond the scope of this article.

Does this mean you should avoid electricity at all costs? Of course not! Just don’t be stupid. At least, not as stupid as we are. Blasted Science has made some incredibly poor decisions with electricity in the past. It’s remarkable that we’re all still alive. Please don’t follow our example.

The post How to Avoid Being Killed by Electricity appeared first on Blasted Science.