Hot Mad Science Posts

DIY Blacksmithing: Forge Your Own Steel at Home!

Metal is a great material to work with. It's rigid, tough, malleable and conductive, but sometimes the part we need doesn't exist in any store. In order to create custom pieces, you need to either melt the metal and cast it in a mold, or heat it until it's soft enough to shape with your hammer. Properly melting metals can be a bit dangerous in our home shop, but we can make a coffee can forge for all of our home blacksmithing needs.

How To: Turn Water into Fuel by Building This DIY Oxyhydrogen Generator

Here's how to build a sexy looking water-fuel generator that will convert your tap water into an extremely powerful, clean burning gas!

How To: Build Your Own Mini Altoids Guitar Amp for About $5

I love making beeps and bloops with the Arduino pitches library, but sometimes archaic 8-bit tunes just don't cut it. Whether you want your robot to terrify your enemies with a demonic synthetic voice, you just need a pocket boom box on the go, or you want to a miniature guitar amp, a simple LM386 amplifier can crank up those signals loud enough to play through any speaker.

How To: Build a Long Range Laser Spy System for Eavesdropping on Your Neighbors

Eavesdropping from a distance can be tricky because it usually requires some sort of bug or transmitter. It's easy to transmit audio through lasers, but you can also use lasers to build a microphone that picks up audio from a distance. LucidScience built the Laser Spy System for about $20. To make your own, you'll need a cheap laser pointer, an NPN phototransistor, a headphone amp, and a few other small pieces listed below. A light-to-sound circuit is installed in a small plastic box with the...

How To: Make a Lethal Traveling Arc of Electricity with a MOT-Powered Jacob's Ladder

With the microwave oven transformer (M.O.T.) salvaged in a previous project, a simple electrical circuit can be rigged to get high voltage arcs to fly outward and upward along a "V" shaped spark gap.

How To: Make Solid Rocket Fuel at Home with Old Newspapers

Old newspapers come in handy for many different uses around the house, from birdcage liners to shipping cushioning and even a little fish cooking. But for backyard rocket scientists like Markus Bindhammer, they're more suitable as an ingredient for rocket propellant.

DIY Polygraph Machine: Detect Lies with Tin Foil, Wire and Arduino

Lying is awesome. From a very young age, children learn that flat out denying the truth gets you out of trouble and helps keep you calm in the face of horror. But what happens when you just have to know if someone, say, used your toothbrush? You could ask them to take an expensive and arduous polygraph test.

How To: Make Slow Burning Fuses from Yarn, Sugar, & Potassium Nitrate

Here's how to make a simple form of a slow burning fuse from materials around the house. WARNING: Ignition of an incendiary or explosive material may not be legal in your area, so check local laws before attempting. Use of this video content is at your own risk.

Spice Rack Explosives: How to Make Gunpowder with Salt & Sugar

The best chemistry experiments are those you can perform with items already laying around your house. With only some sugar, salt substitute and an instant cold pack, you can make your very own gunpowder! Being able to make homemade gunpowder without a trip to the store can be a lifesaver, no matter if it's just for testing out a Civil War-era musket, blowing up stubborn tree stumps, or preparing for battle when imperialists overrun your country.

Inception in Real Life: Make These Lucid Dreaming Glasses and Take Control of Your Dreams

Dreams are like an internal human holodeck. Inside your mind, anything is possible, from your grandest wishes to your worst nightmares. This is all well and good, but what if you could control your dreams and become the omniscient god of a handpicked reality whenever you go to sleep? Inception took this idea to the logical extreme by invading other people's dreams.

How To: Turn a Microwave Oven Transformer into a High Amperage Metal Melter!

In this project, you'll learn step by step how to modify a microwave oven transformer into a high-current device that can pump out 800 amps of electrical current, which is enough amperage to melt metal. If you liked the Metal Melter you saw in my previous project, here's how you can make your own!

How To: Create a PCB Etchant That Automatically Improves After Each Use

Etching your own circuit boards is tons of fun, but etching requires strong chemicals to dissolve the copper plating on blank circuit boards. The normal ferric chloride solution works well, but can be expensive and leaves permanent stains. Luckily, we can whip up our own etchant at home with everyday chemicals! Better yet, our new etchant will turn an eerie green color rather than the dull brown of ferric chloride.

How To: DIY Rocket Propellant! How to Cook Solid Rocket Fuels Using Common Household Ingredients

Cooking isn't something that interests me much, unless it results in a fast burning fuel and a successful rocket launch!

Supercool Science Trick: How to Turn Water into Ice on Command

This is an awesome little science trick that has to be seen to be believed. Simply by emptying a bottle of "supercooled" water into a glass, you can watch it turn into ice right as your pour! It's no magic trick or chemical craziness—it's normal water and you can try it yourself right in your own home.

How To: Make a Hydrogen Fireball from Aluminum Foil and Toilet Bowl Cleaner

Balloons are fun, but the helium ones are always more entertaining. So today, we're going to learn how to make hydrogen gas by combining toilet bowl cleaner with aluminum foil. With hydrogen, you get the same lighter-than-air properties of helium, plus it will explode! Historically, this has proven disastrous, but for our tiny-scale experiments, it will be safe and fun!

How To: Build a Vacation Pet Feeder with a DIY Linear Actuator

If you are a pet owner, going on vacation can be stressful. Usually, you need a friend or neighbor to come over everyday and feed your pets. However, by enslaving robots you can keep your pet happy and enjoy a stress-free holiday.

How To: Find Hidden Blood Splatter Stains on Your Walls with This Infrared Photography Hack

I'm sorry to say, but Dexter Morgan hasn't thought of everything. Just because he's the best blood splatter analyst in the Miami metro area, doesn't mean he can't be taught a thing or two about blood. In fact, I'm sure this is something he'd be glad to know. Spotting a bloodstain is pretty easy at a crime scene, especially when there was no attempt to cover it up. When the scene has been wiped clean, there are still ways for forensic investigators to detect washed away blood, like using a rea...

How To: Design Your Own Custom Arduino Board Microcontroller

Microcontrollers are great. You can do anything from water your garden to catch wildlife trash diggers in the act—and on the cheap. I prefer to use the Arduino microcontroller because of the large and helpful community built around the website. Though it is my favorite, there are some drawbacks to using an Arduino board in every project. It gets expensive, the board can take up too much space, and the rat's nest of breadboard wires are a pain to repair.

How To: Create Your Own Cast and Oogoo to Give Your DIY Gadgets the Shape You Want

I think it's fair to say that every maker yearns for a 3D printer. You can replace circuit board connectors, fix your glasses, create ski grips, and make whole machines out of printed plastic parts—even a 3D printer. But without a 3D printer on hand, you can always resort to Sugru.

Elementary Sputnik Satellites: How to Make Trash Bag Hot Air Balloons

Sputnik was the very first man-made object to be sent into space. Though it was a truly epic accomplishment, all this Soviet sky surfer actually did was transmit a constant beeping noise back to the surface.

How To: Make a Simple Fog Machine to Prank Your Roommates

Like theme music, I always feel that I need more fog in my life. Fog can be useful for many reasons—warding off smaller siblings from your bedroom, keeping curious hands out of your cupboard, and tricking your friends into thinking there's something horribly wrong with their vehicle. So, today we'll be making a very simple fog machine for small scale applications.

How To: Turn Ordinary Water into Explosive Gas That Goes KABOOM!

Maybe not water per-se, but with this simple technique you can turn one of the most abundant materials on earth into a highly explosive gas.

How To: Weapons for the Urban Guerrilla: Make a Taser from a Disposable Camera

The agents of empire do not always arrive with warning. When you are besieged, surrounded, and infiltrated, imagination is often your best weapon against the oppressors. If all you have at hand is some duct tape and a disposable camera, fear not, you have the makings of a powerful taser!

How To: This DIY Double-Bladed 'Stun Sword' Shocks and Slices Simultaneously

When it comes to melee combat, two swords can definitely be better than one. Throw a stun gun on top of that and you've got a seriously terrifying weapon. That's exactly what YouTuber jonathanj9969 did with his homemade double-bladed stun sword.

How To: Light Up the Night Sky with Your Own Burning 'Cincinnati Fire Kite' That Flies by Itself

Not many people fly kites anymore. Most of us don't have the patience or attention span because, let's face it, we're used to smartphones and other gadgets that have games and apps galore to entertain us. Heck, you can even fly a kite on them if you really want.

How To: Stop Bike Thieves Dead in Their Tracks! Make a Magnetically Controlled Bike Alarm

Bikes are a great form of transportation. They use human energy more efficiently than any other machine. You can keep it in your closet or hallway. You can even take it on the train in a pinch. However, this portability is also the bike's biggest draw back. If you own a bike in the city, chances are it will be stolen. Locks barely deter thieves armed with bolt cutters and crowbars. Throw the bike thieves for a loop and make a tilt-sensitive alarm. It will hopefully startle your bike's assaila...

How To: Build a Bomb-Defusing Robot Tank for the Revolution

War leaves a lot of stuff behind. Torn families, delegitimized institutions, mass graves, and unexploded ordinances litter the post occupation landscape. Whether or not you have driven the imperialist out, or are still in the phase of armed resistance, you will need the ability to safely diffuse bombs. My bomb defusing Silvia-bot can do it all. She can catch grasshoppers, cut wires, collect samples, tase enemies and even play chess! Materials

Bat Science: How Realistic Are Batman's Gadgets in Dark Knight Rises?

One of the best things about Christopher Nolan's Batman trilogy is how realistic he makes the caped crusader feel. Unlike the Joel Schumacher or even the Tim Burton versions, Nolan's world seems grounded in some level of scientific fact. But just how close is science to actually being able to replicate some of the Dark Knight's gadgetry?

News: This DIY Mini Tesla Coil Packs 380,000 Volts of Lightning

At one point in time, Tesla coils were actually used for things like wireless telegraphy and electrotherapy, but as technology advanced, they shifted to a slightly more enjoyable purpose—entertainment. What's even more entertaining than using a Tesla coil? Building your own. One of the best portable Tesla coils out there is this mini acrylic version by Daniel Eindhoven, aka TeslaCommander. It's made almost entirely of acrylic plastic, minus the steel sphere, and copper wire and tubing. When t...

How To: Make Homemade Smoke Flares with Fuses

Here's a technique I used to whip up a batch of super cheap and easy to make smoke flares! WARNING: Ignition of an incendiary or explosive material may not be legal in your area, so check local laws before attempting. Use of this video content is at your own risk.

Science Gives You Super Powers: How to Shoot Fireballs from Your Hands

Everyone dreams of having super powers. Flying, invisibility, and x-ray vision are popular, but my favorite is fire power! I've always wanted to be Wheeler from the Captain Planet kids show, and now I can with these handheld fireballs of awesomeness. The fireballs burn at a low temperature, so they are safe to hold in your hand and throw (shoot) at imaginary enemies.

How To: Make a Mini Flamethrower, Exploding Fireball, & Flint Bomb Sparkler with Disposable Lighters

Whether you've got an itch for a mini-flamethrower, a shower of burning sparks, or a exploding ball of flames, these little fireworks-producing lighters may be the answer to your pyrotechnic cravings!

How To: Make Surface-Mount Electronics at Home for Smaller, Cheaper DIY Gadgets

Whenever we make a homemade circuit, we use what are called through-hole components. Any components with long metal leads is a through-hole component. They are great for soldering to, but it's tough to fit enough through-hole resistors and capacitors into a smartphone. To get those last microns, we have surface-mount components for SMDs (surface-mount devices). These are all of those teeny, tiny things you see when you crack open your digital camera or laptop case.

Robot Basics: Using an H Bridge to Move Your Bot Backwards

I love robots. They have the potential to evolve into Asimovian destroyers of the human species, but have only just mastered the art of cleaning my rug. They have an ever increasing cool factor and a growing number of cheap and simple components that let the hobby roboticist reach for the burning miasmas of plasma. But to get to the stars, we need to start with the basics.

How To: Make Dry Ice at Home Using a CO2 Fire Extinguisher

Here's how to make dry-ice at home, or wherever you feel like it! All you need is a pillow case, and a CO2 fire extinguisher.

DIY Solar Power: Make Your Own Diode-Based Solar Panels and Capture the Sun's Energy!

Solar panels are an amazing invention. Catching energy from the Sun before it even enters Earth's food chain, photovoltaics are like an all-natural nuclear power plant. Unfortunately, the constituted parts of a solar panel are rare, valuable, and subject to the coercive forces of market competition.

How To: 10 Things to Do at a Birthday Party with Liquid Nitrogen

If you've got a birthday party to plan for a young budding scientist coming up, a little nitrogen should do the trick. In this project, I'll show you 10 "super cool" tricks with liquid nitrogen that you could try, but probably shouldn't!

How To: Build a Frame for the Mega Solar Scorcher

Here is how you can build a frame for your MEGA SOLAR SCORCHER in under an hour, and for less than $8!! This is effectively a 4 foot magnifying lens that concentrates insane amounts of heat from the sun. What would you do with all this free solar power? My design for this custom "Scorcher Frame" is easy to use, and incredibly cheap to make, as you can see in this step-by-step video.

Glass Cutters Are for Tools: How to Dissolve Glass Using Sodium Hydroxide

Glass is one of the least reactive substances known to chemistry. It is the standard container material for almost all lab chemicals because it's so inert. But there are a couple of substances that have strong reactions with glass. Sodium hydroxide, aka solid drain cleaner or lye, can easily be stored in glass as a solid, but when molten, it reacts violently with glass and can actually dissolve it away! So, the next time you clog up your drains with broken glass beakers and flasks, rest assur...

News: This Real-Life, Working WALL-E Robot Is Absolutely Perfect (And Built Entirely from Scratch)

Want to build your own life-sized, working replica of WALL-E? Be prepared to take on a second job! Mike Senna spent two years perfecting his own version, working 25 hours a week and totaling somewhere around 3,800 hours for the whole project. He had no blueprints to go by, so he spent a lot of time watching the movie over and over to get everything just right. The video below shows some of the construction; skip to about the one minute mark to see WALL-E in action.