7 Deadly Weapons You Should Never Ever Make Out of Harmless Household ItemsS

I write a lot about edgy, semi-dangerous scientific projects. So, I get a lot of suggestions from people who want to share their own ideas for risky home projects. I like the reader engagement, but four times out of five, the ideas are dumb, and borderline deadly. Listen to me: if it involves a pipe, match heads, and gasoline, I guarantee you, it's a bad idea.

Some ideas show more creativity than others. A lot involve diabolical reuses for simple household items. Here are seven such suggestions—oh, and by the way, don't ever make any of them.

7 Deadly Weapons You Should Never Ever Make Out of Harmless Household ItemsS

1. Squirt Gun Flamethrower

I can't begin to tell you how dangerous this is. But it comes up a lot. The idea is to take a Super Soaker, fill it with high-octane gasoline, tape a wire hanger off the muzzle, tape a lit Zippo to the far end of the wire hanger, and voila—instant flamethrower. Do not do it.

This is playing with fire in a bad way. The flame will probably travel backwards, igniting the gasoline in the reservoir. Any "project" involving gasoline that's not in a vehicle's gas tank is incredibly dangerous—roughly on par with messing around with spent plutonium or petri dishes full of the Ebola virus.

7 Deadly Weapons You Should Never Ever Make Out of Harmless Household Items

2. Pie Pan Odd Job Hat

Oddjob, one of the bad guys in the James Bond flick, Goldfinger, wore a hat lined with a hardened steel razor disk in the rim. He used it it as a lethal flying Frisbee. You could make your own—just cut an aluminum pie pan into a doughnut shape with sharpened edges, and glue it onto the brim of your bowler. It might not be as aerodynamically stable and far-flying as Oddjob's original, but it still pretty much guarantees a situation that ends badly for everyone involved.

7 Deadly Weapons You Should Never Ever Make Out of Harmless Household ItemsS

3. The Bleach Bomb

This is a great project if, for some reason, you think you'd like to make a cloud of poison gas to liquefy your lungs. What's in bleach? Sodium hypochlorite. What's in drain cleaner? Hydrochloric acid. When you mix bleach and an acid-containing drain cleaner, a spontaneous chemical reaction occurs:

NaClO + 2 HCl → Cl2 + H2O + NaCl

The reaction produces poisonous chlorine gas and likely leaves unreacted hydrochloric acid as well. Chlorine gas, even small amounts of it, is bad stuff. As WWI graphically demonstrated, it attacks the membranes in your eyes, throat, and nose, and prolonged exposure can cause death by asphyxiation. And hydrochloric acid? Well, that burns just about everything.

7 Deadly Weapons You Should Never Ever Make Out of Harmless Household ItemsS

4. Etch-A-Sketch Thermite

In high school chemistry, you probably learned about exothermic reactions. That's when two chemicals combine to produce byproducts of heat and light.

Not many chemical processes are as gloriously, vigorously, and robustly exothermic as the thermite reaction. Take powdered aluminum (say from the inside of an Etch-a-Sketch) and rusted iron (say from a well-weathered steel wool pad) in just the right proportions and ignite with a sparkler. The reaction that ensues is hot enough to burn through dirt.

7 Deadly Weapons You Should Never Ever Make Out of Harmless Household ItemsS

5. Styrofoam Napalm

Real Vietnam War-era napalm was made by mixing of benzene, gasoline, and polystyrene. The stuff was a hellish mixture that clung to surfaces while it burned, and it was practically inextinguishable. It's hard to imagine a legitimate civilian use for the stuff. (Hell, it's hard to imagine a legitimate military use, for that matter.)

It's possible to come up with something pretty darn close to the vintage napalm by simply dunking Styrofoam in a bucket of gasoline, mixing it around for a while and reserving the leftover goo. Once that goo is lit, good luck trying to put it out.

7 Deadly Weapons You Should Never Ever Make Out of Harmless Household ItemsS

6. Spaghetti-Powered Thermic Lance

Okay, this is actually pretty cool, but still, it's hard for me to recommend that anybody actually do this. In industrial form, thermic lances are iron or steel pipes filled with thinner iron and aluminum rods, bathed in pressurized oxygen. In an oxygen-rich environment, the iron and aluminum can actually be ignited, producing a sustained high-temperature flame.

You've seen thermic lances in movies—when bank robbers cut through 9 inches of steel to break into a bank vault, they will attach one end of the lance to an oxygen tank, and light the rods with an electric arc. The ensuing reaction burns hot enough to melt concrete.

You can make your own, though, using uncooked spaghetti to replace the iron and aluminum, and a short length of 3/4-inch pipe for the housing. You can connect the sealed pipe to a canister of oxygen, which costs about 10 bucks at Home Depot. The spagetti-powered lance works like the industrial one: the oxygen-rich environment inside the pipe allows the normally slow burning pasta to burn like crazy, producing a high-temperature, energetic flame.

7 Deadly Weapons You Should Never Ever Make Out of Harmless Household ItemsS

7. Flesh-burning Maglite Laser

Myriad YouTube videos show how to make a retina-melting, flesh-burning portable laser from a discarded DVD burner and Maglite flashlight. If you remove the laser diode from the burner, then swap it out for the bulb of the Maglite, you essentially turn the flashlight into a handheld, intensely concentrated laser. It takes some soldering skills, but you wind up with a tool that there are just so many reasons you shouldn't own.

William Gurstelle, aka @wmgurst, is the author of Absinthe and Flamethrowers, The Practical Pyromaniac, and he contributes to Make and Popular Mechanics magazines. The second edition of his book, Backyard Ballistics, comes out today!

Photo Credits:
Opener. Matthew Taylor, Gizmodo Shooting Challenge: Fire
1. Squirt Gun Flamethrower
2. 007.net
3. Shutterstock
4. Amazon
5. William Gurstelle
6. Hackaday via YouTube
7. Laser flashlight hack