[other traps]

Diet Coke & Mentos Trap, Version 2

This is a Diet-Coke-and-Mentos trap that I designed based on an earlier version designed by Jay. Like its predecessor, the lid is connected to multiple tripwires, each of which is connected to its own bottle of Diet Coke with a stack of Mentos waiting to drop. The biggest difference is that this version uses two-liter bottles instead of 12 oz bottles (with a bigger chest to hold them), though I also improved the firepower by shrinking the exit hole and adding more Mentos per bottle.

Equipment

• One ice chest, preferably with a hinged lid. It should be tall enough to hold at least one and preferably several two-liter bottles of soda.
• Numerous two-liter bottles of Diet Coke. Ideally you'll want enough bottles to not leave any wiggle room in your chest, though you can also use something as filler to keep them from sloshing around much as you set your trap. I went for seven two-liter bottles, which was the maximum number my ice chest could hold.
• Plastic soda bottle tops (one per bottle). Ideally you should use the tops off of old soda bottles so that the ones you'll be arming won't lose their fizz, but if you don't have a handy supply it's not a big deal.
• Mentos. I went for about five per bottle.
• Thread. Use black if you're feeling cruel.
• Rubber bands, one per bottle.
• Heavy washers, bolts or fishing sinkers, one per bottle. Ideally, it should be heavy so it drags the mints to the bottom of the coke bottle. (Note: if you use a lead sinker, don't let people drink remaining diet coke after the trap goes off.)
• Straight pin or wire with an eyelet at one end. I used some pins from my wife's earing-making kit, but you can also make your own out of electrical wire, needles or even paper clips.
• Duct tape. Because all traps need duct tape.

Construction

First, pull the little blue plastic seals off of the insides of your bottle tops so they don't get in the way of your drill. Then drill a hole in the top of each bottle top, about the diameter of a pencil. While you're drilling, drill a small hole in each of your Mentos mints, just big enough to thread.

Next, tie a heavy washer or fishing sinker to the end of your thread, and thread about five mints along the line. Do this for each bottle. This will be the thread that wraps around the firing pin and keeps the Mentos from falling into the bottle before the pin is pulled. This is the "mint line."

Now take a separate thread and tie it to the straight pin. This will be the thread that attaches to the lid of the ice chest and pulls the pin out when the chest is opened. Attach the pin to the side of your bottle cap with the rubber band. Do this for each bottlecap. This is your "firing line."

Now draw a strand of mints up through the hole in the top of each bottlecap so the mints rest inside the cap. Bring the line back down (around the rubberband) and wrap the line around the lower end of the firing pin. It should be tight enough that the thread doesn't come loose on its own, but not so tight that it can't slip free when the pin is pulled. In particular, you want to make sure that the thread doesn't wind up caught under the rubberband when the pin is pulled. Depending on the kind of thread used, you might experiment with different ways of tying off until you find one that keeps the mints secure but still lets them drop once the pin gets pulled.

Now you're ready to set up the chest itself. Put your unopened bottles of Diet Coke into the chest, and surround them with enough other bottles such that they're wedged in tight and won't jostle. That's it for the preparation phase — you'll want to wait until arming the trap before doing the last bit of construction so that the Diet Coke doesn't lose its fizz before anyone tries opening the chest.

Arming

The trap is fairly stable once set, but you'll want to arm shortly before firing because the diet coke will lose its fizz after being opened for a few hours. Open your bottles, and replace the bottlecaps with your modified caps, with the mints dangling inside the bottle. Be sure the mints dangle completely above the diet coke.

Next comes the tricky part. Wedge the lid open a few inches, and duct tape the firing lines (the ones tied to the pin, not the ones with the mints) to the lid of the chest. I just used a single piece of tape that went all the way across the top of the lid, but if you're feeling especially cruel you can use a separate piece of tape for each pin. In the photos below, I had switched out the black thread for a thicker, white string just because it was easier to deal with. (In retrospect this was a mistake, as they also tended to get stuck on the caps rather than let the mints drop when the pin was pulled.)

Disarming

The basic strategy is the same as the previous version: wedge the box open a crack, tape the wedge in place, then cut all the threads. Again, the trickiest part is cutting the thread without pulling it, because the caps tend to be pretty sensitive. With the previous version, after a couple near-firings with a pair of somewhat dull scissors I upgraded to using a long-necked grill lighter to burn through all the threads (just be sure you don't set the box on fire). Also, make doubly sure you get all the threads — it's easy to miss one if it happens to be dark and the threads happen to be black.

Of course, you can also simply have the neighborhood kids come over and ask them to open the chest for you.